Bank Statement Reconciliation - Error 20, then Fatal Error 177

Hi,

I have an issue where I am receiving the following error messages, but only after I have imported an MT940 Statement:

Error 1 = Application Error. @X3.TRT/GESUSER$adx (1384) Error 20 : File nonexistent mid$

I then choose OK to this and I get a second error:

Error 2 = Fatal Error (177). For an unknown reason, the server has refused to establish a new session.

I then choose OK to this and the Bank Statement Reconciliation screen appears as it should.

However, if I have NOT just uploaded an MT940 statement, I can go into the screen no problem and it works without giving any of the error messages.

Does anyone have any ideas please?

Thank you.