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C#, MAS-90, Attempted to read or write protected memory error on OdbcDataAdapter.Fill(dataTable)

I am writing a Windows Forms application that needs to query 2 fields from a MAS-90 database. For this we use the MAS 90 32-bit ODBC Driver by ProvideX called SOTAMAS90. Here is the code I use to retrieve a DataTable from the MAS-90 database.
public static DataTable getDatatable(string qry)
{
DataTable dt = new DataTable();
using (OdbcConnection conn = new OdbcConnection(GetSQLConnection()))
{
try
{
OdbcCommand cmd = new OdbcCommand(qry, conn);
cmd.CommandType = CommandType.Text;
conn.Open();
OdbcDataAdapter adpt = new OdbcDataAdapter(cmd);
adpt.Fill(dt);
cmd.Dispose();
conn.Close();
conn.Dispose();
}
catch (OdbcException e) { conn.Close(); }
catch (AccessViolationException ae) { conn.Close(); }
catch (UnauthorizedAccessException ue) { conn.Close(); }
}
return dt;
}
On line adpt.Fill(dt) I get the following exception:
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
This was working just fine yesterday. Today Visual Studio is telling me that this is an Unhandled AccessViolationException even though you can clearly see the try/catches. I had to add <legacyCorruptedStateExceptionsPolicy enabled="true"/> to my config file just for the exception to be caught in the try/catch.
The other strange thing is I am able to connect to the database and run the same exact query (which is just selecting 2 fields from a table) using the ODBC Query Tool by Jaime De Los Hoyos M. (Available here)
Any help at resolving this issue is greatly appreciated. Please let me know if you need additional information.
I also wanted to add that I have tried:
Targeting x86 in my app as the Driver is 32-bit
Giving permissions to the directory where the database is stored
Restarting PC
Changing query to add parameters with cmd.Parameters.AddWithValue("#PARAM", "Value")

I was able to resolve my issue. The database was stored on a server to which my PC had a mapped drive to. For whatever reason, the mapping broke for the MAS 90 32-bit ODBC Driver. This was strange because I was still able to access the network drive's files via File Explorer and I was also able to query the table via the ODBC query tool I mentioned (which uses the same ODBC driver). I discovered this when I wanted to change the Database Directory field (seen below) and it kept telling me the path was invalid or inaccessible (even though it was accessing it for the ODBC query tool).
Anyway, I remapped the network drive, then deleted and recreated the SOTAMAS90 DSN and it worked again.

Insert integer value into SQL Server database from C#

I am trying to insert an integer value into a SQL Server database as below when I run the program there are no any errors, but the table doesn't get updated with values. I have searched on the internet and I am doing the same can anyone help to find what I am doing wrong.
Note: I already defined "connectionString" as a string on the form class
private void btnUpdate_Click(object sender, EventArgs e)
{
int totalincome=600;
int totaldeductions = 10;
connectionString = ConfigurationManager.ConnectionStrings["BudgetApp.Properties.Settings.MainDataBaseConnectionString"].ConnectionString;
con = new SqlConnection(connectionString);
con.Open();
cmd = new SqlCommand("INSERT INTO Totals(TotalIncome, TotalDeductions) VALUES (#TotalIncome, #TotalDeductions)", con);
cmd.Parameters.AddWithValue("#TotalIncome", totalincome);
cmd.Parameters.AddWithValue("#TotalDeductions", totaldeductions);
cmd.ExecuteNonQuery();
MessageBox.Show("Done !!");
}

The whole AttachDbFileName= approach is flawed - at best! When running your app in Visual Studio, it will be copying around the .mdf file (from your App_Data directory to the output directory - typically .\bin\debug - where you app runs) and most likely, your INSERT works just fine - but you're just looking at the wrong .mdf file in the end!
If you want to stick with this approach, then try putting a breakpoint on the myConnection.Close() call - and then inspect the .mdf file with SQL Server Mgmt Studio Express - I'm almost certain your data is there.
The real solution in my opinion would be to
install SQL Server Express (and you've already done that anyway)
install SQL Server Management Studio Express
create your database in SSMS Express, give it a logical name (e.g. MainDataBase)
connect to it using its logical database name (given when you create it on the server) - and don't mess around with physical database files and user instances. In that case, your connection string would be something like:
Data Source=.\\SQLEXPRESS;Database=MainDataBase;Integrated Security=True
and everything else is exactly the same as before...
Also see Aaron Bertrand's excellent blog post Bad habits to kick: using AttachDbFileName for more background info.

Code Seems correct,Perhaps you are checking the wrong DB?. I would add a Try/catch for exceptions. And remember to close connection after executing query. Regards

check your database column datatype,use try catch.
and try to replace cmd.Parameters.AddWithValue("#TotalIncome", totalincome); to cmd.Parameters.Add("#Number", SqlDbType.Int).Value = totalincome;
try
{
int totalincome=600;
int totaldeductions = 10;
connectionString = ConfigurationManager.ConnectionStrings["BudgetApp.Properties.Settings.MainDataBaseConnectionString"].ConnectionString;
con = new SqlConnection(connectionString);
con.Open();
cmd = new SqlCommand(#"INSERT INTO Totals(TotalIncome, TotalDeductions) VALUES (#TotalIncome, #TotalDeductions)", con);
cmd.Parameters.Add("#Number", SqlDbType.Int).Value = totalincome;
cmd.Parameters.Add("#Number", SqlDbType.Int).Value = totaldeductions;
//cmd.Parameters.AddWithValue("#TotalIncome", totalincome);
//cmd.Parameters.AddWithValue("#TotalDeductions", totaldeductions);
cmd.ExecuteNonQuery();
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}

SQL Server CE two way sync with remote Access database

I'm working on a pretty special, legacy project where I need to build an app for PDA devices under Windows Mobile 6.5. The devices have a local database (SQL Server CE) which we are supposed to sync with a remote database (Microsoft Access) whenever they are docked and have network access.
So the local database using SQL Server CE works fine, but I can’t figure out a way to sync it to the Access database properly.
I read that ODBC and OLEDB are unsupported under Windows Mobile 6.5, most ressources I find are obsolete or have empty links, and the only way I found was to export the local database relevant tables in XML in the hope to build a VBA component for Access to import them properly. (and figure out backwards sync).
Update on the project and new questions
First of all, thanks to everyone who provided an useful answer, and to #josef who saved me a lot of time with the auto path on this thread.
So a remote SQL Server is a no go for security reasons (client is paranoid about security and won't provide me a server). So I'm tied to SQL Server CE on the PDA and Access on the computer.
As for the sync:
The exportation is fine: I'm using multiple dataAdapters and a WriteXML method to generate XML files transmitted by FTP when the device is plugged back in. Those files are then automatically imported into the Access database. (see code at the end).
My problem is on the importation: I can acquire data through XML readers from an Access-generated file. This data is then inserted in a dataset (In fact, I can even print the data on the PDA screen) but I can't figure out a way to do an "UPSERT" on the PDA's database. So I need a creative way to update/insert the data to the tables if they already contains data with the same id.
I tried two methods, with SQL errors (from what I understood it's SQL Server CE doesn't handle stored procedures or T-SQL). Example with a simple query that is supposed to update the "available" flag of some storage spots:
try
{
SqlCeDataAdapter dataAdapter = new SqlCeDataAdapter();
DataSet xmlDataSet = new DataSet();
xmlDataSet.ReadXml(localPath +#"\import.xml");
dataGrid1.DataSource = xmlDataSet.Tables[1];
_conn.Open();
int i = 0;
for (i = 0; i <= xmlDataSet.Tables[1].Rows.Count - 1; i++)
{
spot = xmlDataSet.Tables[1].Rows[i].ItemArray[0].ToString();
is_available = Convert.ToBoolean(xmlDataSet.Tables[1].Rows[i].ItemArray[1]);
SqlCeCommand importSpotCmd = new SqlCeCommand(#"
IF EXISTS (SELECT spot FROM spots WHERE spot=#spot)
BEGIN
UPDATE spots SET available=#available
END
ELSE
BEGIN
INSERT INTO spots(spot, available)
VALUES(#spot, #available)
END", _conn);
importSpotCmd.Parameters.Add("#spot", spot);
importSpotCmd.Parameters.Add("#available", is_available);
dataAdapter.InsertCommand = importSpotCmd;
dataAdapter.InsertCommand.ExecuteNonQuery();
}
_conn.Close();
}
catch (SqlCeException sql_ex)
{
MessageBox.Show("SQL database error: " + sql_ex.Message);
}
I also tried this query, same problem SQL server ce apparently don't handle ON DUPLICATE KEY (I think it's MySQL specific).
INSERT INTO spots (spot, available)
VALUES(#spot, #available)
ON DUPLICATE KEY UPDATE spots SET available=#available
The code of the export method, fixed so it works fine but still relevant for anybody who wants to know:
private void exportBtn_Click(object sender, EventArgs e)
{
const string sqlQuery = "SELECT * FROM storage";
const string sqlQuery2 = "SELECT * FROM spots";
string autoPath = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase); //get the current execution directory
using (SqlCeConnection _conn = new SqlCeConnection(_connString))
{
try
{
SqlCeDataAdapter dataAdapter1 = new SqlCeDataAdapter(sqlQuery, _conn);
SqlCeDataAdapter dataAdapter2 = new SqlCeDataAdapter(sqlQuery2, _conn);
_conn.Open();
DataSet ds = new DataSet("SQLExport");
dataAdapter1.Fill(ds, "stock");
dataAdapter2.Fill(ds, "spots");
ds.WriteXml(autoPath + #"\export.xml");
}
catch (SqlCeException sql_ex)
{
MessageBox.Show("SQL database error: " + sql_ex.Message);
}
}
}

As Access is more or less a stand-alone DB solution I strongly recommend to go with a full flavored SQL Server plus IIS to setup a Merge Replication synchronisation between the SQL CE data and the SQL Server data.
This is described with full sample code and setup in the book "Programming the .Net Compact Framework" by Paul Yao and David Durant (chapter 8, Synchronizing Mobile Data).
For a working sync, all changes to defined tables and data on the server and the CE device must be tracked (done via GUIDs, unique numbers) with there timestamps and a conflict handling has to be defined.
If the data is never changed by other means on the server, you may simply track Device side changes only and then push them to the Access database. This could be done by another app that does Buld Updates like described here.
If you do not want to go the expensive way to SQL Server, there are cheaper solutions with free SQLite (available for CE and Compact Framework too) and a commercial Sync tool for SQLite to MSAccess like DBSync.
If you are experienced, you may create your own SQLite to MS ACCESS sync tool.

SQLIte unable to open database

I just started working on a sample application that only calls some tables on my SQLite database, and I have managed to solve other issues that have happened except this one.
Although I have searched for this, none of the suggested solutions for the connectionstring, permission issues and etc seem to be valid and working for me. For the permissions, I added the Everyone user with full control, and I still get the same error.
Below is the code that I am trying to execute:
// calling function
void getRecords2()
{
MySqlLite.DataClass ss = new MySqlLite.DataClass();
DataTable dt = ss.selectQuery("select * from english_words");
}
// the SQLite class that execute the code
using System.Data;
using System.Data.SQLite;
namespace MySqlLite
{
class DataClass
{
private SQLiteConnection sqlite;
public DataClass()
{
//This part killed me in the beginning. I was specifying "DataSource"
//instead of "Data Source"
sqlite = new SQLiteConnection(#"Data Source=C:\testwork\db\MrPick.sqlite3.db;Version=3;FailIfMissing=True");
}
public DataTable selectQuery(string query)
{
SQLiteDataAdapter ad;
DataTable dt = new DataTable();
try
{
SQLiteCommand cmd;
sqlite.Open(); //Initiate connection to the db
cmd = sqlite.CreateCommand();
cmd.CommandText = query; //set the passed query
ad = new SQLiteDataAdapter(cmd);
ad.Fill(dt); //fill the datasource
cmd.Dispose();
sqlite.Dispose();
}
catch (SQLiteException ex)
{
//Add your exception code here.
}
sqlite.Close();
return dt;
}
}
}
Note: I used the following assembly:
ADO.NET SQLite Data Provider
Version 1.0.82.0 September 3, 2012
Using SQLite 3.7.14
Originally written by Robert Simpson
Released to the public domain, use at your own risk!
Official provider website: http://system.data.sqlite.org/
I really appreciate your help on this.

Per your comment, you're getting a "Unable to open database file" error because you're pointing the code at a file that doesn't exist.
A "Table not found" error means it found the database, but not the table you were looking for. On the other hand, "Unable to open database file" means that it couldn't even find the database, and didn't even bother looking for a table. You're much closer to it working correctly when you're getting "Table not found".
You should change the path back to match the file on disk, then use a tool like the Firefox SQLite Manager to confirm that the english_words table does exist in your database.
If it doesn't, you should create it with that tool, and if it does, you should post another question here about the "Table not found" error.
Hopefully that helps.

When I ran into this error I had to set parseViaFramework in the SQLiteConnection constructor to true.
SQLiteConnection connection = new SQLiteConnection(connectionString, true);
connection.Open();

I was facing same issue on the shared hosting server,
My C# code was able to read data from SQLIte db file.
But while add / update data it was throwing Error "unable to open database"
I tried many options suggested on stackoverflow
But after referring
https://stackoverflow.com/a/17780808/2021073
and
https://www.sqlite.org/pragma.html#pragma_journal_mode
I tried adding journal mode=Off; to the Connection string
and it worked for me
sample code
SQLiteConnection connection = new SQLiteConnection("Data Source=G:\dbfolder\sqlite3.db;Version=3;Mode=ReadWrite;journal mode=Off;", true);

DSN Util C#(Won't create)

I was following this other post --> C# DSN Util
So I have the following code. (Slightly Modified)
OdbcConnection DbConnection = null;
try
{
DbConnection = new OdbcConnection(
"DataSourceName=NEWDSN;"+
"Driver=SQL Server;" +
"Description=New DSN;" +
"Server=<NameofServer>;");
DbConnection.Open();
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.ReadKey();
System.Environment.Exit(0);
}
Everything seems to work fine, I get no errors but nothing is created? I have tried troubleshooting with the following techniques
I am able to create one when doing it manually in the ODBC Admin tools
When adding "DatabaseName=blah;"
I have tried many things in this field but am unable to produce anything.
EDIT:
Hmm, there may not be a way to create one using this code. DBConnection.Open seems to be my only decent option. Is it even possible to create one that will appear in the ODBC Data Source Admin?

The code and example you are using is for opening a DSN that has already been created, not for actually creating them in the first place.
You probably need something more like this example
http://www.codeproject.com/KB/database/DSNAdmin.aspx