Error -8003 u201CObeserver dll version mismatchu201D.

Question

I have an SBO installation sitting on a server called SVR.  The SBO version is 2005 PL44 sitting on SQL 2000 to reflect one of our current customers.   On my laptop I have a VS2005 C# DI-API project that attempts to connect to the companies on SVR.  I also run an SBO installation on my laptop (SBO version 2005 PL50).
I get the error -8003 u201CObeserver dll version mismatchu201D.
To try and resolve this I made sure that:
  1. the reference in my C# DI-API project was to a valid SAPbobsCOM2005.dll (i.e. a PL44 version)
  2. I removed %TEMP%/ SM_OBS_DLL so that it would refresh with the Observer.dll from the SVR machine (I think it downloads from SBO_Common on SVR)
  3. I stopped the licensing manager service (set it to manual) on my laptop and rebooted just so I could clear any in process references to my PL50 version.
I then retried to connect and got the same error. 
I checked the OBServerDLL.dll that went back into the %TEMP%\SM_OBS_DLL directory and the version was PL44.
I canu2019t understand why; if I am referencing a PL44 SAPbobsCOM2005.dll in my DI-API C# project, and the Observer.dll that gets loaded from the SVR machine is a PL44 version that I get a version mismatch.
Does anyone know the reason or can anymore explain the architecture concerning the versioning so I can resolve my issue?
Thanks

Answer 1

Thanks Jitin,
Very helpful but I still have the problem.  I tried the folowing as the link suggested...
1. Locate the Temp folder by going to Start -> Run and type %temp%.
2. Locate the SM_OBS_DLL folder here and delete it.
3. Uninstall the DI API from Add/Remove Programs.
4. Reboot your PC
5. Install the DI API from your current patch. (Download patch, extract it and then browse to Packages\DI API and run setup.exe)
6. Run the Upgrader Common again (From the same patch as above - very important!). Browse to Packages\Upgrader Common and run setup.exe. This will update the SBO-COMMON to this patch level again. You will not lose any data.
... which makes a lot of sense - and I would have thought would have solved my problem.  A colleague in the office CAN connect using the same DIAPI application.  He is running a laptop with Version 2007 on it.  Perhaps the major difference in versions is working to his advantage.@^%#$!
I would like to understand the architecture so I can methodically troubleshhot the process. 
I have a Backward and Forward compatibility guide that shows the OBServer.dll getting downloaded from the Server and into process memory - but it's a bit lighton detail.
Are there any more comprehensive documents that can be accessed from SAP or from other sources.  I've been trawling the internet but no cigar as yet...
Thanks