rinai abinaya 

It's important you attach the error stacks when you get error messages like this as the underlying detail sometimes points towards a problem that the "quick fixes" would not resolve.  The way to do that is click on these small disk symbols and save the files to your desktop.  Then attach them to your reply.  DO NOT copy and paste the content into your replay because this will probably trigger the spam prevention feature in the community and your post won't get posted:

1. click these disk symbols to save the full detail behind the error
2. click these links to the knowledgebase as they might also give you a solution now... worth trying!

In the meantime, here's the catch all fix that may or may not work!

Close Trados Studio and then delete this folder:

c:\Users\%username%\AppData\Roaming\Trados\Trados Studio\Studio18\

Then restart Trados Studio and see if that helped.