title: Releasing New Version of Tlb and When Tlb Needs To Be Re-Referenced
body: <p>I have a C# dll and generarted a tlb using regasm. I have given a utility spreadsheet to the users which uses this tlb. The tlb is unregistered and registered (using regasm.exe) everytime a new version of our application is released.</p>
  
  <p>However, at  times, when the user is using the spreadsheet after a new release, it throws a 'activex component cannot create instance' error, exactly on the line of code where I create an object of a type. I fix this just by, removing and adding the tlb reference back. (In vba mode-tools-reference-uncheck the tlb-save-and again add). However this is painful since I cannot do this for all users.</p>
  
  <p>I did several tests to replicate the scenario. Like changing the version number of dll and re-registering, adding new methods to interfaces and re-registering. But in all the cases, the spreadsheet works fine without having to remove and re-add the tlb reference.</p>
  
  <p>So, I am confused what could be the scenario where the tlb has to be re-added as reference in the spreadsheets and what could be the probable cause of this. Any help is appreciated.</p>
  
  <p>Thanks,
  Mani</p>