Failed on start - workflow error

I was trying to create a basic workflow with one single "LogtoHistory" activity. But when i tried to start that workflow after associating it with a List. It was failing with the error message "Failed on start"

I tried to debug it after attaching it with the w3wp.exe process. But it was not hitting the break points and the break points were saying the error message
"No symbols have been loaded for this document."
This gave me a clue about the error. I checked the assembly information in the workflow.xml file and found that schema i used to create the workflow.xml put the version of the assembly as 3.0.0.0 . I changed it to correct version and executed the workflow again. It worked fine.

So, If the workflow is failing with "Failed on start" it means there is some mismatch in the assembly information. But if the workflow is giving the error "Failed on Start (Retrying)" there may be some other issues.