ODP.net works locally but not on other computer - c#

I created a C# project on my computer that uses ODP.net, I imported the reference of Oracle.DataAccess. On my PC, I try to do a connection to the Database and it works normally, however, if I copy the .exe file of my application in another computer, it does not work and I receive the following error:
System.IO.FileNotFoundException: Could not load file or assembly
'Oracle.DataAccess, Version=4.112.3.0, Culture=neutral,
PublicKeyToken=89b483f429c47342' or one of its dependencies. The
system cannot find the file specified. File name: 'Oracle.DataAccess,
Version=4.112.3.0, Culture=neutral, PublicKeyToken=89b483f429c47342'
Why doesn't C# encapsulate all the files needed in the .exe? What can I do to make this program work regardless of the executing computer?

As of request by Vito, here is my comment as an answer:
I suggest to not use the "classic" ODP.NET which has dependencies on additional installed ODP components on the system, but instead use the purely managed version of ODP.NET.
For the managed ODP.NET you have a single assembly (i.e. a DLL) that you can ship with your application (e.g. in the "bin" folder if it is an ASP.NET application) and you're done.
Just to make it complete, the connection string in my cases looks something like:
<add
name="ora"
connectionString="Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=MyServer)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=XE))); User Id=MyUser; Password=MyPassword"
providerName="system.data.oracleclient" />
The managed version was really a huge improvement in terms of ease-of-use in my projects.

you must have installed version of the Oracle Database on each machine where you intend to install your application.
Another option is to go to Oracle and download just drivers.
Download from Oracle, then you need to include them with your project, reference this dll.

Please see the answer to a similar question I had. Mainly this problem is about oracle.dataaccess.dll, it's build platform (32 or 64) and presence of some of it's dependencies (like OraOps11w.dll). These things should be checked to see if are present and configured correctly. It would get big in deployment! Of-course if you are calling the library at machine level (not app level) from different applications, you should check if it's registered in GAC too.
Edit: In it's simplest form:
1 - You need to have these dlls in your app directory: OraOps11w.dll, oci.dll, orannzsbb11.dll and oraociei11.dll.
2 - You have to add a reference to Oracle.DataAccess.dll.
Where can one get these?
1 - From the installation directory of you Oracle Client (not Server), if you already had installed the oracle client (including ODP.NET).
2 - If you have installed ODT.NET.
3 - By getting ODP.NET (preferably the zip archive, not the install package).

There are TONS of possible causes to your problem here. I would first start by copying the entire folder than contains the .EXE file, and not just the .EXE file itself. There are things in this folder that your .EXE needs in order to run. Also, I would check the dependencies on the computer that is not working with the program Dependency Walker. Things can go wrong if you develop on a 32-bit and try to run on a 64-bit. Things can go wrong if you develop on Windows and try running on MAC. There is a lot that can change from one computer to the next, and your code must be ready for that. Dependency walker can tell you if you aren't connecting to certain dependancies (mostly .DLL's) correctly. If you go into the release folder that contains your EXE, if there exists any .DLL files in that same directory, these .DLL's are likely needed on any computer that will try and run this program.

Related

Why my Windows form application not connecting to mysql in another computer? [duplicate]

I am working on Desktop application with c# and Data base MySQL. When I install its installer on my machine it works fine but when I install it on other machine its give following exception when try to access DB. I am using MySQL.Data.dll to communicate with MySQL.
Could not load file or assembly 'MySql.Data, Version=6.2.2.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d' or one of its dependencies. The system cannot find the file specified.
and MySql.Data.dll file in present in Project's folder in Program files folder
Actually when I run it from its folder in Program file it run fine with no error but When i try to run it from its shortcut in Start Menu it gives that error.
It sounds i am 2 years late answering this post but it might be helpful for those who are still facing this issue, so here is my finding dated 1st April 2012 5pm EST:
I had the same issue with one of my web application. And I found the said issue arises when you do:
Copy & Paste the MySql.Data.dll somewhere in a folder.
You have a copy of any version of MySql.Data.dll in GAC
Though application works fine on your development machine as it can see the files but when you deploy it on some other machine it actually brings the run time error.
In my case, the VS2008 always pointed me with the same error as you mentioned. I then did this:
Removed the local copy reference of the dll
Referenced the DLL found in GAC
And set the property "Copy Local" to "True" of the DLL by right-clicking->properties.
Edit:
Somebody asked "Where is GAC?":
http://msdn.microsoft.com/en-us/library/yf1d93sz(v=vs.110).aspx
Does the shortcut in the Start Menu set the working directory correctly? (I suspect that this is the most likely answer)
Is there a different/incorrect version of MySql.Data.dll installed in the GAC (Global Assembly Cache)? I've seen this give similar error messages before.
Is MySQL.data.dll present in the same directory as the .exe file ?
If so does that MySQL.data.dll have the proper version/public key that the .exe file is looking for ?
When this thing happens to me it is usually one out of two things:
Make sure that MySql.Data is present on the machine where you get the error. (It unbelievable how often a files turns out to be missing :-) )
If MySql.Data is a mixed mode (native and managed code) 32 bit DLL. And you executable specifies "Any CPU". On a 64 bit machine with 64 bit .NET this will fail with error message you got. A solution is to specify "x86" as target for the executable.
Tommy's reason is very valid:
My project was referencing to an older version of the MySql.Data.dll compared to what was actually installed on my development machine. This will result in the same error.
Check you .config file:
And compare that verisonNr to the versionNr of the file when you would add a new reference to it.
Solution:
1) remove the line from your config file and re-add the reference
2) or uninstall the MySql .net connector and install the version which your project is referencing to.
I had this issue too, for me it was recreating the connection strings in project settings. They were configured for a previous version of the MySQL connector.
I was having the same problem in a web application (C#).
I managed to solve it by changing the web.config file, it was referencing version 6.2.2.0, and my dll was version 8.0.25.0.
<system.data>
<DbProviderFactories>
<remove invariant="MySql.Data.MySqlClient" />
<add name="MySQL Data Provider" invariant="MySql.Data.MySqlClient"
description=".Net Framework Data Provider for MySQL"
type="MySql.Data.MySqlClient.MySqlClientFactory, MySql.Data,
Version=8.0.25.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" />
</DbProviderFactories>
</system.data>
Make sure that the MySql.Data DLL you put in the Project's folder is the correct version (6.2.2.0 in this case).

Possible reasons for assembly / file not found?

I'm working in a team that has created a solution. In the solution we have 4 projects (data access, business logic and unit tests and common things).
BL references DA and CT
CT references DA
UT references BL and CT
Now whenever I rebuild it brings no errors. On my collegues PC it works without a hitch but on my PC whenever I try to run an unit test I get the following error (translated manually into english so any typos are my fault while writing this question):
{"The file or assembly \"MyWorkspaceName.MySolutionname.CT,
version=0.2.0.0, Culture=neutral, PublicKeyToken=null\" or a reference
of it was not found. The system cannot find the given
file.":"MyWorkspaceName.MySolutionname.CT, version=0.2.0.0,
Culture=neutral, PublicKeyToken=null"}
As that version and name exists (it is the common things part I manually checked if it exists) and I also checked the refernces inside of the CT if they are correct.....I'm not sure what could be a possible reason for it not working for me (but working on my collegues PC).
Thus my question would be: What could be possible reasons for that error message?
Update:
CT is now found but when I try to access the DA from BL it says the same error as before just with DA instead of the CT (ran from the UT part).
When I run the SAME methods from a console application project created within the same solution, they work without throwing any error.
There are three possibilities,
Different CPU architectures, if your colleague's PC is x64 and yours is x86 then DLL reference setup in projects might differ and that could give this error.
Different folder structures.
Different third party references, see the details below.
Are you sure you have installed every third party tools/libraries that are there on your colleague's PC?
Most probably third party references should be added as NuGet packages but if your project references third party assembly which in turn references another assembly installed via some installer and which is absent on your machine, you may get similar error. I had similar problems and some native libraries do not show up in error as dependencies unless you turn on assembly log and investigate.
Did you try to delete /obj and /bin folder before rebuilding? Sometimes there are old assembly reference caches which mess the build process.
Here is a PowerShell script for recursive erase of /bin and /obj folders. Just run it in the main solution folder.
Get-ChildItem .\ -include bin,obj -Recurse | foreach ($_) { remove-item $_.fullname -Force -Recurse }
Another possible problem that I have encountered is when there is a difference between assemblies installed in the GAC and locally downloaded NuGet packages. - Your VS gets the DLL from GAC but on your team mates computers the DLL comes from NuGet and it is different version.
To get the assembly binding information in VS : Tools -> Options -> Projects And Solutions -> Build And Run -> MS Build project build output verbosity -> Set to Diagnostic and when you build Copy-Paste the diagnostic info into notepad++ and search for 'error' and 'conflict' then resolve.
Usually if I can't solve such issues in a meaningful amount of time I go for help to Process Monitor
In your case I would add a not too restrictive filter such as: Path contains .dll and look for failure results during application launch. This might reveal what actual dll files could not be found and places were they were looked for.
Visual Studio works on a trust system, meaning you have to explicitly trust network drives. have you tried to copy the project to your local hard drive to see if it works?
Here is the article from microsoft on how to change the trusts using the CasPool.exe tool.
Caspol.exe (Code Access Security Policy Tool)
Just a few notes about this so you don't miss anything. There is different trusts for both 32-bit and 64-bit applications, so make sure you apply the trust to both to avoid any issues.
Before you go through the trouble of this tool, I would highly recommend that you copy to your local hard drive first and see if that is indeed the problem.

MEF Different Assembly Version Loading Issue

I have a bit of a conundrum with MEF.
I have an installer and configuration application shell which uses MEF to load individual installer components. This gives an end user the ability to select from whatever components have been placed into the install distributable.
The first install components which were written to use this used version 11 of SQLServer SMO libraries. Installing against either 2008R2 or 2012 works fine. (lets call this component A)
I have another team migrating code to a new component but that code uses version 10 of the SQLServer SMO, RMO, and SSIS (DTS) libraries. (lets call this component B)
When MEF goes to load component B I get a LoaderExceptionFailure for one of the SQLServer DLLs (Microsoft.SqlServer.Replication). It actually gives a FileNotFoundException (listing the DLL). The DLL exists in the component's directory. It is the correct version 10.
The shell application already has version 11 files in it.
Is there a way I can tell the application context what to do? Is there a way I can tell the component to load any specific libraries it needs?
I want to assume that each component can specify something "Associated.Library, Version=1.0.0.0, publickey=abcdef123456789, culture=none".
The reason the CLR (not MEF) cannot find the assembly is because it is neither in the GAC, not in the places were the current AppDomain is setup to probe for assemblies.
One way to deal with this kind of problem is to add the missing assembly to the GAC.
Another approach is to add the folder containing the missing assembly to the probing paths of your application. If you don't mind deploying these assemblies in the application base folder (the one containing your executable) then do so. Otherwise you can add deploy it in a sub folder of your application base folder and add the folder to the privatePath element of your app.config.
You will find more information on the article: How the Runtime Locates Assemblies.

Failed to grant minimum permission requests when calling C# library from C++/CLI DLL from local console app

This question follows on from Assembly does not allow partially trusted callers when using a custom resolver
Thanks to the solution in that question I am now able to call into a C# Library on a network share from a local console application (with no changes to CasPol)
I now need to take the next step which is calling the C# Library from another mixed C++/CLI DLL that is in the same folder on the network as the C# Library. The C++/CLI DLL will be called by the local console application.
I'm using the same custom handler in question above (ie. with evidence) that works when calling into a C# library fromn a local console application.
When calling into the C++/CLI library from the local Console application I get the following exception:
Could not load file or assembly 'MyCplusplusCLILib, Version=0.0.0.0,
Culture=neutral, PublicKeyToken=null' or one of its dependencies.
Failed to grant minimum permission requests. (Exception from HRESULT:
0x80131417)
If I fully trust the network location it works correctly however I do not understand why I need to grant this trust when according to changes in 3.5 SP1 the Intranet should no longer require FullTrust to be applied to it (all libraries are compiled for .NET 3.5 in the Visual Studio options)
The cases where you don't get FullTrust are listed at the bottom of this blog post:
Assemblies loaded from a subdirectory of the share where the .exe was launched from
Assemblies loaded from shares other than the one where the main .exe was launched
Any assembly loaded on a machine with the LegacyMyComputer registry value set to 1
Any assembly loaded into a CLR host, including assemblies loaded into Internet Explorer as controls.
Any assembly loaded from shares by an application that was launched from the "real" MyComputer zone.
Sounds like your case is number 5. Copying the .exe to the same network directory would be a workaround.
I faced an issue with DLL permissions. DLL files downloaded from internet get blocked in windows due to security/trust issue. They needed to be manually unblocked before any part of code can use these dependency.
To unblock:
Go to properties & click the "unblock" button and the problem may be solved.

A problem regarding dll inheritance

I have created a dll that will be used by multiple applications, and have created an installer package that installs it to the program files, as well as adds it to the Global Assembly Cache.
The dll itself uses log4net, and requires a xml file for the logging definitions.
Therefore when the installer is run, the following files get copied to the install directory within program files:
The main dll that I developed
- The Log4Net.dll
- the Log4Net.xml file
I am now experiencing a problem. I have created a test console application for experimentation. I have added my dll as a reference, and set the 'local copy' flag to false.
When I compile the test console exe however, I noticed that it has copied the log4net.dll and log4net.xml files to the bin directory. And when running the test console, it appears that it will only work if the log4net.dll is in the same directory as the exe. This is dispite the fact that the test console application does not use log4net, only the dll that was added as a reference does.
Is there some way to have it so that the log4net.dll & xml files used will be the ones that were installed to the program files, rather than any application needed to copy over local copies? The applications that will be using my dll will not be using log4net, only the dll that they are referencing uses it.
Many thanks
Don't install into the Global Assembly Cache! Even if your library dll is used by multiple applications each should have it's own local copy. Otherwise you get into a whole world of pain for saving a few KB of disk space.
Always copy the required dlls locally. If you are really sure that the application won't need it you can simply delete the unnessesary dlls later or don't include them in the installer. But if your application will call ANY reference there it will crash at runtime. So best option is to leave them there (after all they WERE referenced for a reason).
No, it's not possible (at least not without much efford) to have .Net load dlls from arbitrary locations on the disk. And it should be this way (look up DLL-hell if you want to know why).
I suspect your problem is the configuration. You must use fully qualified names if you want it to work from the GAC. As per the documentation at http://logging.apache.org/log4net/release/faq.html:
"When loading an assembly from the GAC the fully qualified assembly name, including the version, culture and public key must be specified. This is in the standard syntax supported by System.Type.GetType. See the next FAQ on how to get the version and public key for an assembly."
I managed to resolve this by adding Log4net.dll to the GAC as well. It will now run without needing a local copy the dll.
It does however require a local copy of the XML file, to correctly log.

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