external component has thrown an exception / Unknown exception when generating layout for segment xxxxx (internal row xxxxx)

When I try to translate a word file 

these are the messages that I get.

"external component has thrown an exception" 

"Unknown exception when generating layout for segment X (internal row X)"

 

 

 

 

If I click OK

 

I get this..

 

"Object reference not set to an instance of an object" 

 

 

I tried to uninstall Trados and reinstall (twice) and I get the same message..

Can you help me solve this problem ?