DB2Connection DLL error VB.NET

[seraieis]

Hi all,

I've been working on a few home-grown apps for my department, one of which connects to a DB2 database and generates reports from it. It has worked splendidly on my machine, but this morning when I testing it on another users machine, it crashed.

I’ve gotten 2 separate exceptions:
1) System.EntryPointNotFoundException: Unable to find an entry point named ‘nmpTraceOn’ in DLL ‘db2app.dll’.
2) System.DLLNotFoundException: Unable to load DLL ‘db2app.dll’. The specified procedure could not be found.

When I tried to package the DLL in the install file, I still received the same error. I would think it works on my machine because I had the DB2 developers kit installed. Is there a way to get the program to link to that DLL, or am I going to have to get the kit installed on everyone’s machine?

This is the code that generates the error:

        Dim cn As New DB2Connection( _
            db.cnString & "UID=" & txtUser.Text & _
            ";PWD=" & txtPass.Text)

Thanks!

[Plater]

I think you need to register the dll with windows first.
regdll or something I think. Google how to register .DLL files with windows and you should find it.
I think that needs to be done before you can use it?

[seraieis]

I tried to register the DLL on the user's machine, but it was not successful. Any other ideas? I'm about out of them....

[Plater]

What did the failure say? I am a little confused at how you were using the classes contained withen.
Is this a .NET dll or a COM dll?
You don't reegister .NET dll's with windows but with the CLR in the global assambly cash (GAC). But maybe that only applies to web applications.
Regardless, what type of DLL is it?

[seraieis]

I should have been more specific. Registering the DLL didn't fail, but when I reran the program, it still didn't work.

All the DB2 .NET functions work perfectly on my computer. I did an inventory of two users computers, and in the c:\Program Files\SQLLIB\bin folder neither of them have the db2app.dll. I tried simply copying this file to the folder, but, again, that didn't work.

How would I register a DLL with the cache? I am not famliar with the GAC.

[Plater]

I am thinking the DB2 DLL you are using has some sort of hardpath* in it looking for COM stuff maybe?

* Could also include things like needing the registry entries



Have you tried just using the OleDB namespace and ignoring specific db2 stuff?
http://www.codeproject.com/KB/database/DotnetDb2.aspx

[Curtis Rutland]

In case you go the way Plater suggested and need it:
This article has more information on using OleDb.

/shameless plug of my own article

Also check connectionstrings.com to find the right connection string.

[seraieis]

Thank you both for those responses. I tried it, and it worked a lot smoother on my machine that the DB2 libraries, but i received the following error on another user's machine:

System.InvalidOperationException: The 'IBMDADB2' provider is not registered on the local machine.
   at System.Data.OleDb.OleDbServicesWrapper.GetDataSource(OleDbConnectionString constr, DataSourceWrapper& datasrcWrapper)
   at System.Data.OleDb.OleDbConnectionInternal..ctor(OleDbConnectionString constr, OleDbConnection connection)
   at System.Data.OleDb.OleDbConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningObject)
   at System.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(DbConnection owningConnection, DbConnectionPoolGroup poolGroup)
   at System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)
   at System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
   at System.Data.OleDb.OleDbConnection.Open()
   at WindowsApplication1.Form1.ExecQuery()
 

When I tried to register the DLL with the user's machine, it said something along the lines of "the specified module cannot be found", even though i used an absolute path. This may be a permissions issue, in which case I could have local support come up and register the DLL with her machine.

Any other ideas before I involve support? Thanks!

[Plater]

This

The 'IBMDADB2' provider is not registered on the local machine.

sounds like there is no DB2 drivers installed on that machine, which is roughly were we started this problem.
You check to see if IBM has any free drivers for it?

[seraieis]

There are DB2 drivers on their machine. I ran a directory map of their computer and they both have the files, and the ibmdadb2.dll are in the Windows registry.

Is there a way to hardcode where a VB.NET app looks for a DLL? If that's the case, i could package the DLL with the program and distribute it that way.

[jhaxo]

There are DB2 drivers on their machine. I ran a directory map of their computer and they both have the files, and the ibmdadb2.dll are in the Windows registry.

Is there a way to hardcode where a VB.NET app looks for a DLL? If that's the case, i could package the DLL with the program and distribute it that way.

Did you run the db2 client install on the target machine? I have done these kind of apps and it always worked smoothly for me.
The installation will take care of registration and perhaps any arcane files that might need to be there plus its all nice and legal.

[jhaxo]

Thank you both for those responses. I tried it, and it worked a lot smoother on my machine that the DB2 libraries, but i received the following error on another user's machine:

System.InvalidOperationException: The 'IBMDADB2' provider is not registered on the local machine.
   at System.Data.OleDb.OleDbServicesWrapper.GetDataSource(OleDbConnectionString constr, DataSourceWrapper& datasrcWrapper)
   at System.Data.OleDb.OleDbConnectionInternal..ctor(OleDbConnectionString constr, OleDbConnection connection)
   at System.Data.OleDb.OleDbConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningObject)
   at System.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(DbConnection owningConnection, DbConnectionPoolGroup poolGroup)
   at System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)
   at System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
   at System.Data.OleDb.OleDbConnection.Open()
   at WindowsApplication1.Form1.ExecQuery()
 

When I tried to register the DLL with the user's machine, it said something along the lines of "the specified module cannot be found", even though i used an absolute path. This may be a permissions issue, in which case I could have local support come up and register the DLL with her machine.

Any other ideas before I involve support? Thanks!

there might be some required dlls causing registration to fail. also, just a thought, is there a microsoft driver you can use instead? or another ibm driver you can use such as odp.net? i forgot to mention that in my last post, i think its available freely and you would install it together with your program on each client.

[seraieis]

I've contacted local support to get the DB2 Connect package installed on the users computer to see if that solves the problem. However, with the way things work in this company, it probably won't get installed until next week, so I'll post again once I can test it.

Regardless, I want to thank everyone for their advice and suggestions. I'll let you all know how it goes :)


Dan

[seraieis]

The DB2 Connect package did the trick!

Again, I want to thank you for all your help in this. You guys are amazing!

[brianbward]

It's nice to see that I'm not the only one creating homegrown applications. But I think I'm in the same boat with db2app.dll.

I have something installed on my PC called DB2 Universal Database Personal Edition. It comes with utilities like Command Center and Control Center. I get the feeling it's not the same thing as the DB2 Connect Package . Could you give me a little more information about that software so I know what to ask for?

Thank you.

-Brian