An unhandled error when starting Paint dot NET

Hi,
I have been using Paint.Net for a long time and working perfectly but now when I try to use this program I get the following error message. I could not understand what happened to this while I did nothing wrong. I made a drawing and using the internet and the next day I received this annoying error message. How can I solve this issue? Please help me. Thanks.

There was an unhandled error, and Paint.NET must be closed. Refer to the file ‘pdncrash.log’, which has been placed on your desktop, for more information.
