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AccessViolationException thrown by OleDbConnection.Open()

I am getting a System.AccessViolationException error when trying to use the .Open() method on my OleDbConnection variable. But, confoundingly, it doesn't seem to happen when I run my code on a different computer.
My code is for a service that I want running on a server. It appears to work correctly when I run it on my personal computer, but it throws the AccessViolationException error when I try running it on the server.
Code Versions:
I am writing in C# using Visual Studios 2019 on Windows 10
OleDbConnection is from "Assembly System.Data, Version=4.0.0.0"
ADOX is from "Assembly Interop.ADOX, Version=2.8.0.0", System.Runtime.InteropServices
ADODB is from "Assembly Interop.ADODB, Version=2.8.0.0", System.Runtime.InteropServices
My code:
internal static bool CreateMDB(MySchemaClass schema, string filePath)
{
OleDbConnection conn = null;
bool status = true;
string connectionString = string.Format("Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0}", filePath);
try
{
// Setup new file
catalog.Create(connectionString);
((ADODB.Connection)catalog.ActiveConnection).Close();
conn = new OleDbConnection(connectionString);
conn.Open(); // <-- Error occurs here
// Write to new file
WriteDataToFile(schema, conn);
}
catch (Exception ex)
{
status = false;
}
finally
{
if (conn != null)
conn.Close();
}
return status;
}
StackTrace:
The best lead I have found so far is this post, but I'm a bit hazy about how to proceed from that starting point.

To programmatically create an Access database do the following:
Add reference to Microsoft ADO Ext. 6.0 for DDL and Security
In VS menu, click Project
Select Add Reference
Click COM
Check Microsoft ADO Ext. 6.0 for DDL and Security
CreateAccessDatabase
public static string CreateAccessDatabase(string fullyQualifiedAccessFilename, string dbPassword = "")
{
string connectionString = String.Format(#"Provider = Microsoft.ACE.OLEDB.12.0; Data Source = {0}", fullyQualifiedAccessFilename);
if (String.IsNullOrEmpty(fullyQualifiedAccessFilename))
{
throw new Exception("Error (CreateAccessDatabase) - Database filename is null or empty.");
}
if (!String.IsNullOrEmpty(dbPassword))
{
connectionString = String.Format(#"Provider = Microsoft.ACE.OLEDB.12.0; Data Source = {0};Jet OLEDB:Database Password='{1}'", fullyQualifiedAccessFilename, dbPassword);
}
//create new instance
ADOX.Catalog cat = new ADOX.Catalog();
//create Access database
cat.Create(connectionString);
//close connection
cat.ActiveConnection.Close();
//release COM object
System.Runtime.InteropServices.Marshal.ReleaseComObject(cat);
GC.Collect();
cat = null;
return String.Format("Database created '{0}'", fullyQualifiedAccessFilename);
}
Usage:
string result = string.Empty;
SaveFileDialog sfd = new SaveFileDialog();
sfd.Filter = "Access Database 2000-2003 (*.mdb)|*.mdb|Access Database 2007 (*.accdb)|*.accdb";
if (sfd.ShowDialog() == DialogResult.OK)
{
//create Access database
result = CreateAccessDatabase(sfd.FileName);
}
To programmatically create a table in an Access database:
Add using statement:
using System.Data.OleDb;
CreateTableProduct:
public static int CreateTableProduct(string fullyQualifiedAccessFilename, string dbPassword = "")
{
int result = 0;
string connectionString = String.Format(#"Provider = Microsoft.ACE.OLEDB.12.0; Data Source = {0}", fullyQualifiedAccessFilename);
if (!String.IsNullOrEmpty(dbPassword))
{
connectionString = String.Format(#"Provider = Microsoft.ACE.OLEDB.12.0; Data Source = {0};Jet OLEDB:Database Password='{1}'", fullyQualifiedAccessFilename, dbPassword);
}
string sqlText = string.Empty;
sqlText = "CREATE TABLE Product ";
sqlText += "(ID AUTOINCREMENT not null primary key,";
sqlText += " Name varchar(50) not null,";
sqlText += " Price currency, Quantity integer);";
using (OleDbConnection con = new OleDbConnection(connectionString))
{
//open connection
con.Open();
using (OleDbCommand sqlCmd = new OleDbCommand(sqlText, con))
{
//execute command
result = sqlCmd.ExecuteNonQuery();
}
}
return result;
}
Resources:
ADO Features for each Release
Which Access file format should I use?
CREATE TABLE statement (Microsoft Access SQL)
System.Data.OleDb Namespace

The underwhelming answer to the problem is that my server was lacking some of the files my personal computer had, and only needed the correct files installed.
The missing piece in this case was the Microsoft Access Database Engine 2016 Redistributable, which I ended up finding here. Running that executable on my server got the needed files and everything worked after that.

Error: DisconnectedContext was Detected in asp.net C#

I am facing a problem while uploading an excel sheet using oledb. Couple of weeks ago, it was working perfectly so I moved to different module.
But when I am testing and debugging the application now it is throwing an error.
Someone please look into this as I am not able to resolve this issue, also, their is no resolution posted when I searched on google as well....
Error: DisconnectedContext was Detected
Transition into COM context 0x673dd0 for this RuntimeCallableWrapper failed with
the following error: The object invoked has disconnected from its clients.
(Exception from HRESULT: 0x80010108 (RPC_E_DISCONNECTED)). This is typically
because the COM context 0x673dd0 where this RuntimeCallableWrapper was
created has been disconnected or it is busy doing something else. Releasing
the interfaces from the current COM context (COM context 0x673d18). This
may cause corruption or data loss. To avoid this problem, please ensure
that all COM contexts/apartments/threads stay alive and are available for
context transition, until the application is completely done with the
RuntimeCallableWrappers that represents COM components that live inside them.
My Code: For FileUpload
string filefullpath = null;
try
{
string filepath = Server.MapPath("~/BulkUploadFile/");
string filename = fuDatabaseFile.FileName;
string filetype = Path.GetExtension(filename);
string filenamewithoutextension = Path.GetFileNameWithoutExtension(filepath);
string append = DateTime.Now.ToString("yyyyMMddHHmmssfffFFF");
string newfilename = filenamewithoutextension + append + filetype;
filefullpath = filepath + newfilename;
fuDatabaseFile.SaveAs(filefullpath);
}
catch (Exception ex)
{
}
Code for ExcelConnectivity:
FileUpload();
string excelconnectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0; Data Source=" + FileUpload() + ";Extended Properties=Excel 12.0;Persist Security Info=False";
using (OleDbConnection excelcon = new OleDbConnection(excelconnectionstring))
{
using (OleDbCommand command = new OleDbCommand("", excelcon))
{
command.CommandText = "Select * from [Sheet1$]";
excelcon.Open();
using (OleDbDataReader reader = command.ExecuteReader())
{
DataTable table = new DataTable();
table.Columns.Add("Name");
table.Columns.Add("EmpID");
}
}
}

The Microsoft Office Access database engine could not find an object

I'm trying to copy data from excel to sql server but facing the following error.
The Microsoft Office Access database engine could not find the object 'sheet1$'. Make sure the object exists and that you spell its name and the path name correctly.
My code is:
protected void importdatafromexcel(string filepath)
{
string sqltable = "PFDummyExcel";
string exceldataquery = "select EmployeeId,EmployeeName,Amount from [Sheet1$]";
string excelconnectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + filepath + ";Extended Properties=Excel 12.0;Persist Security Info=False";
string sqlconnectionstring = System.Configuration.ConfigurationManager.ConnectionStrings["HRGold"].ConnectionString;
SqlConnection con = new SqlConnection(sqlconnectionstring);
OleDbConnection oledb = new OleDbConnection(excelconnectionstring);
OleDbCommand oledbcmd = new OleDbCommand(exceldataquery, oledb);
oledb.Open();
OleDbDataReader dr = oledbcmd.ExecuteReader();
SqlBulkCopy bulkcopy = new SqlBulkCopy(sqlconnectionstring);
bulkcopy.DestinationTableName = sqltable;
while (dr.Read())
{
bulkcopy.WriteToServer(dr);
}
oledb.Close();
}
Please tell me how i solve this..

This error is raised because of you are trying to access sheet (which name is sheet1) in excel file. By default first sheet name is "sheet1" but user have either rename this name or delete this sheet.
To resolved this issue first of all you have to get all sheet name from excel file, then you have to pass this sheet name in your above code to import data.
string filePath = "your file path";
string excelconnectionstring = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + filepath + ";Extended Properties=Excel 12.0;Persist Security Info=False";
OleDbConnection Connection = new OleDbConnection(excelconnectionstring);
DataTable activityDataTable = Connection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
if(activityDataTable != null)
{
//validate worksheet name.
var itemsOfWorksheet = new List<SelectListItem>();
string worksheetName;
for (int cnt = 0; cnt < activityDataTable.Rows.Count; cnt++)
{
worksheetName = activityDataTable.Rows[cnt]["TABLE_NAME"].ToString();
if (worksheetName.Contains('\''))
{
worksheetName = worksheetName.Replace('\'', ' ').Trim();
}
if (worksheetName.Trim().EndsWith("$"))
itemsOfWorksheet.Add(new SelectListItem { Text = worksheetName.TrimEnd('$'), Value = worksheetName });
}
}
// itemsOfWorksheet : all worksheet name is added in this
so you can use itemsOfWorksheet[0] as sheet name in-place of "sheet1"

I had similar issue, I sorted it out by
Saving the excel file from fileuploader to a temporary folder inside website folder.
Using path to that file in my connection string
Rest all was same and now the error: The Microsoft Office Access database engine could not find the object 'sheet1$' was gone.

How can I read the rows of an Excel csv or xls file into an ASP.NET app from a remote location using C#?

Here's my situation. I'm designing a program that takes Excel files (which may be in csv, xls, or xlsx format) from a remote network drive, processes the data, then outputs and stores the results of that process. The program provides a listbox of filenames that are obtained from the remote network drive folder using the method detailed in the accepted answer here. Once the user selects a filename from the listbox, I want the program to find the file and obtain the information from it to do the data processing. I have tried using this method to read the data from the Excel file while in a threaded security context, but that method just fails without giving any kind of error. It seems to not terminate. Am I going about this the wrong way?
Edit - (Final Notes: I have taken out the OleDbDataAdapter and replaced it with EPPlus handling.)
I was able to scrub sensitive data from the code, so here it is:
protected void GetFile(object principalObj)
{
if (principalObj == null)
{
throw new ArgumentNullException("principalObj");
}
IPrincipal principal = (IPrincipal)principalObj;
Thread.CurrentPrincipal = principal;
WindowsIdentity identity = principal.Identity as WindowsIdentity;
WindowsImpersonationContext impersonationContext = null;
if (identity != null)
{
impersonationContext = identity.Impersonate();
}
try
{
string fileName = string.Format("{0}\\" + Files.SelectedValue, #"RemoteDirectoryHere");
string connectionString = string.Format("Provider=Microsoft.ACE.OLEDB.14.0; data source={0}; Extended Properties=Excel 14.0;", fileName);
OleDbDataAdapter adapter = new OleDbDataAdapter("SELECT * FROM Sheet1", connectionString);
DataSet ds = new DataSet();
adapter.Fill(ds, "Sheet1");
dataTable = ds.Tables["Sheet1"];
}
finally
{
if (impersonationContext != null)
{
impersonationContext.Undo();
}
}
}
Additional Edit
Now xlsx files have been added to the mix.
Third Party
Third party solutions are not acceptable in this case (unless they allow unrestricted commercial use).
Attempts - (Final Notes: Ultimately I had to abandon OleDb connections.)
I have tried all of the different connection strings offered, and I have tried them with just one file type at a time. None of the connection strings worked with any of the file types.
Permissions
The User does have access to the file and its directory.

Your connection string might be the issue here. As far as I know, there isn't 1 that can read all xls, csv, and xlsx. I think you're using the XLSX connection string.
When I read xls, i use the following connection string:
#"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + sFilePath + ";Extended Properties='Excel 8.0;HDR=YES;IMEX=1;'"
Having said that, I recommend using a 3rd party file reader/parser to read XLS and CSV since, from my experience, OleDbDataAdapter is wonky depending on the types of data that's being read (and how mixed they are within each column).
For XLS, try NPOI https://code.google.com/p/npoi/
For CSV, try http://www.codeproject.com/Articles/9258/A-Fast-CSV-Reader
For XLSX, try EPPlus http://epplus.codeplex.com/
I've had great success with the above libraries.

Is it really important that you use an OleDb interface for this? I've always done it with Microsoft.Office.Excel.Interop, to wit:
using System;
using Microsoft.Office.Interop.Excel;
namespace StackOverflowExample
{
class Program
{
static void Main(string[] args)
{
var app = new Application();
var wkbk = app.Workbooks.Open(#"c:\data\foo.xls") as Workbook;
var wksht = wkbk.Sheets[1] as Worksheet; // not zero-based!
for (int row = 1; row <= 100; row++) // not zero-based!
{
Console.WriteLine("This is row #" + row.ToString());
for (int col = 1; col <= 100; col++)
{
Console.WriteLine("This is col #" + col.ToString());
var cell = wksht.Cells[row][col] as Range;
if (cell != null)
{
object val = cell.Value;
if (val != null)
{
Console.WriteLine("The value of the cell is " + val.ToString());
}
}
}
}
}
}
}

As you will be dealing with xlsx extension, you should rather opt for the new connection string.
public static string getConnectionString(string fileName, bool HDRValue, bool WriteExcel)
{
string hdrValue = HDRValue ? "YES" : "NO";
string writeExcel = WriteExcel ? string.Empty : "IMEX=1";
return "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=" + fileName + ";" + "Extended Properties=\"Excel 12.0 xml;HDR=" + hdrValue + ";" + writeExcel + "\"";
}
Above is the code for getting the connection string. First argument expects the actual path for file location. Second argument will decide whether to consider first row values as column headers or not. Third argument helps decide whether you want to open the connection to create and write the data or simply read the data. To read the data set it to "FALSE"
public static ReadData(string filePath, string sheetName, List<string> fieldsToRead, int startPoint, int endPoint)
{
DataTable dt = new DataTable();
try
{
string ConnectionString = ProcessFile.getConnectionString(filePath, false, false);
using (OleDbConnection cn = new OleDbConnection(ConnectionString))
{
cn.Open();
DataTable dbSchema = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
if (dbSchema == null || dbSchema.Rows.Count < 1)
{
throw new Exception("Error: Could not determine the name of the first worksheet.");
}
StringBuilder sb = new StringBuilder();
sb.Append("SELECT *");
sb.Append(" FROM [" + sheetName + fieldsToRead[0].ToUpper() + startPoint + ":" + fieldsToRead[1].ToUpper() + endPoint + "] ");
OleDbDataAdapter da = new OleDbDataAdapter(sb.ToString(), cn);
dt = new DataTable(sheetName);
da.Fill(dt);
if (dt.Rows.Count > 0)
{
foreach (DataRow row in dt.Rows)
{
string i = row[0].ToString();
}
}
cn.Dispose();
return fileDatas;
}
}
catch (Exception)
{
}
}

This is for reading 2007 Excel into dataset
DataSet ds = new DataSet();
try
{
string myConnStr = "";
myConnStr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=MyDataSource;Extended Properties=\"Excel 12.0;HDR=YES\"";
OleDbConnection myConn = new OleDbConnection(myConnStr);
OleDbCommand cmd = new OleDbCommand("select * from [Sheet1$] ", myConn);
OleDbDataAdapter adapter = new OleDbDataAdapter();
adapter.SelectCommand = cmd;
myConn.Open();
adapter.Fill(ds);
myConn.Close();
}
catch
{ }
return ds;

C# import excel filesheet to sql database error

I have met the error: Multiple-step OLE DB operation generated errors. Check each OLE DB status value, if available. No work was done. I'm using SQL Server 2005 and Visual Studio 2005.
I met this error during the import of an excel filesheet to a table in my sql table. Below is my code:
#region Using directives
using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.OleDb;
using System.Data.SqlClient;
using System.IO;
using System.Configuration;
#endregion Using directives
namespace CSASPNETExcelImportExport
{
public partial class ExcelImport : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
// Get the row counts in SQL Server table.
protected int GetRowCounts()
{
int iRowCount = 0;
using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["Data Source=<IP>;Initial Catalog=SOD;Persist Security Info=True;User ID=<username>;Password=<password>"].ToString()))
{
SqlCommand cmd = new SqlCommand("select count(*) from <database>", conn);
conn.Open();
// Execute the SqlCommand and get the row counts.
iRowCount = (int)cmd.ExecuteScalar();
}
return iRowCount;
}
// Retrieve data from the Excel spreadsheet.
protected DataTable RetrieveData(string strConn)
{
DataTable dtExcel = new DataTable();
using (OleDbConnection conn = new OleDbConnection(strConn))
{
// Initialize an OleDbDataAdapter object.
OleDbDataAdapter da = new OleDbDataAdapter("select * from <database>", conn);
// Fill the DataTable with data from the Excel spreadsheet.
da.Fill(dtExcel);
}
return dtExcel;
}
// Import the data from DataTable to SQL Server via SqlBulkCopy
protected void SqlBulkCopyImport(DataTable dtExcel)
{
using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["Data Source=<ip>;Initial Catalog=SOD;Persist Security Info=True;User ID=<username>;Password=<password>"].ToString()))
{
// Open the connection.
conn.Open();
using (SqlBulkCopy bulkCopy = new SqlBulkCopy(conn))
{
// Specify the destination table name.
bulkCopy.DestinationTableName = "<database>";
foreach (DataColumn dc in dtExcel.Columns)
{
// Because the number of the test Excel columns is not
// equal to the number of table columns, we need to map
// columns.
bulkCopy.ColumnMappings.Add(dc.ColumnName, dc.ColumnName);
}
// Write from the source to the destination.
bulkCopy.WriteToServer(dtExcel);
}
}
}
protected void btnImport_Click(object sender, EventArgs e)
{
// Before attempting to import the file, verify
// that the FileUpload control contains a file.
if (fupExcel.HasFile)
{
// Get the name of the Excel spreadsheet to upload.
string strFileName = Server.HtmlEncode(fupExcel.FileName);
// Get the extension of the Excel spreadsheet.
string strExtension = Path.GetExtension(strFileName);
// Validate the file extension.
if (strExtension != ".xls" && strExtension != ".xlsx")
{
Response.Write("<script>alert('Please select a Excel spreadsheet to import!');</script>");
return;
}
// Generate the file name to save.
string strUploadFileName = "~/UploadFiles/" + DateTime.Now.ToString("yyyyMMddHHmmss") + strExtension;
// Save the Excel spreadsheet on server.
fupExcel.SaveAs(Server.MapPath(strUploadFileName));
// Generate the connection string for Excel file.
string strExcelConn = "";
// There is no column name In a Excel spreadsheet.
// So we specify "HDR=YES" in the connection string to use
// the values in the first row as column names.
if (strExtension == ".xls")
{
// Excel 97-2003
strExcelConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Server.MapPath(strUploadFileName) + ";Extended Properties=\"Excel 8.0;HDR=Yes;\"";
//if the above doesn't work, you may need to prefix OLEDB; to the string, e.g.
//strExcelConn = "OLEDB;Provider=Microsoft.Jet.OLEDB.4.0;Data Source=<URL>" + Server.MapPath(strUploadFileName) + ";Extended Properties=\"Excel 8.0;HDR=Yes;\"";
}
else
{
// Excel 2007
strExcelConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=<URL>" + Server.MapPath(strUploadFileName) + ";Extended Properties=\"Excel 12.0 Xml;HDR=YES\"";
}
DataTable dtExcel = RetrieveData(strExcelConn);
// Get the row counts before importing.
int iStartCount = GetRowCounts();
// Import the data.
SqlBulkCopyImport(dtExcel);
// Get the row counts after importing.
int iEndCount = GetRowCounts();
// Display the number of imported rows.
lblMessages.Text = Convert.ToString(iEndCount - iStartCount) + " rows were imported into Person table";
if (rblArchive.SelectedValue == "No")
{
// Remove the uploaded Excel spreadsheet from server.
File.Delete(Server.MapPath(strUploadFileName));
}
}
}
}
}
Is it because my connectionstring error?
I have changed my connection strings as of what Nathan suggested. Now I met the following error:
http://i.stack.imgur.com/nWyte.png
What error is it this time? D:

It looks like you actually have several things wrong with your connection strings. For one thing, Excel connection strings should not include an "Initial Catalog", and they should include a Data Source referring to the file, not a server.
Try this instead:
// There is no column name In a Excel spreadsheet.
// So we specify "HDR=YES" in the connection string to use
// the values in the first row as column names.
if (strExtension == ".xls")
{
// Excel 97-2003
strExcelConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Server.MapPath(strUploadFileName) + ";Extended Properties=\"Excel 8.0;HDR=Yes;\"";
//if the above doesn't work, you may need to prefix OLEDB; to the string, e.g.
//strExcelConn = "OLEDB;Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Server.MapPath(strUploadFileName) + ";Extended Properties=\"Excel 8.0;HDR=Yes;\"";
}
else
{
// Excel 2007
strExcelConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + Server.MapPath(strUploadFileName) + ";Extended Properties=\"Excel 12.0 Xml;HDR=YES\"";
}
Fyi, http://connectionstrings.com is a good resource for these kind of things.

Try removing "Persist Security Info=True" from your connection strings.
http://support.microsoft.com/kb/269495