Winamp file conversion if file already is mp3

[AmazingDreams]

Hi,

This is so annoying.
I want to convert all my files to mp3, however, 50% of my files (800 in total) already are mp3. During the conversion, every time the converter encounters an mp3 file it says: source and target file are identical (freely translated from dutch).
Which means, that I have to press 'ok' about 400 times. I tried pressing and holding 'enter' but then it broke off the conversion as soon as the first non-mp3 file was encountered.

I looked into the settings of the convertor, but there was no option for 'what to do if file already exists'?
I could get an autoclicker, but I was wondering if any other person encountered this error and found a good way around it.

Thanks in advance
AmazingDreams