Problem caused the program to shut down

Hi, I am not very technical but a couple of days ago i had a virus so downloaded Norton Power Eraser and that fixed the problem but now i am having problems with my programs, for example my MYOB is working fine but if i try to save a file to disk or email a file i get the message "the program has stopped working and will be shut down" I have changed the compatibility setting in properties but it hasn't helped.

If someone can give me some advice it would be great as i have a customer waiting for an invoice to be emailed to them.

Cheers

Welcome
Run a full and updated anti virus scan
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Go into clean boot mode and see if the problem persisits. If it does not follow the clean boot procedure to solve
How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7