activex control can't create object c# dll in windows 10/7

Question

hi MS Team,

i created a dll with vs2015 in c# in windows 7 32 bits and working fine up to now.
i changed my pc where i created the dll to new laptop windows 10 64 bits .
now iam trying to improve the last dll to resolve some errors but it work fine only in my pc .
i tested it in other 3 pc, 2 pc with win10 and other (win7 this pc is already running old version of this dll and the new not work)

always same error : activex control can't create object .
dll is registered correctly and contains the same namespace ,class , public method entries with old version .
the different only in postgres connection.

thanks in advance.

Answer 1

On Windows 10 start VS2015 as Administrator. This is important so that VS2015 can perform the COM registration during the build process for the C# Class Library project.

Class Library Project Properties - 32-bit build with COM registration

In this example the C# namespace is CSharpServer and the class is Hello. When this project is built by VS2015 it will perform COM registration and create a ProgId of CSharpServer.Hello in the registry under HKCR. For example,

The GUID in the example is the CLSID that VS2015s COM registration will create in the 32-bit view of the registry under the WOW6432Node subkey of HKCR. For example, this is the 32-bit registration of the CLSID key in the registry -

Note the WOW6432Node subkey in the path above

Run script from 64-bit Command prompt. Error is expected for 32-bit server.

Run script from 32-bit Command prompt. Successful execution results.

Answer 2

On a 64-bit system a COM Server can be registered as either a 64-bit server or a 32-bit server. On a 32-bit Win7 system this isn't something you previously had to manage. But now that you are transitioning to 64-bit Win10 you need to be aware of the issues. It is likely that your COM server is registered as a 32-bit server on the Win10 system. However, if you open a command prompt and try to run a script the process that runs the script is probably a 64-bit process. This would cause the error you have experienced.

For example, if I have a 32-bit server registered this is the result from a 64-bit process trying to run a script -

Now if I explicitly run the 32-bit script engine using the command "c:\windows\syswow64\cscript tester.vbs" the problem is avoided because a 32-bit process is using a 32-bit server.

Other options include starting a 32-bit command prompt using "c:\windows\syswow64\cmd.exe" or using a 64-bit COM server and ensuring it is registered in the 64-bit view of the registry.

Answer 3

hi RLWA32-6355

iam sorry, but still the same error.

i programmed other dll in 32 bit but the same error .