Problems with exporting audio files on Audacity as MP3

Please can I get some hlep with resolving this issue. I am not very familiar with coding aand debugging. I have attached a PDF with the error message I am getting each time I try to export an audio file as MP3.

Thaank you,
Pat
Assertion failed.pdf (53 KB)

Hi! Everybody,
I ssorted the issue. I deleted all audacity programs and cleaned my registry. I reinstalled an earlier version which worked perfectly and now everything is working beautifully.