Custom board icon upload problems

I have tried several times to upload and image for a custom board icon to replace the one I already have. I have tried deleting the old one etc. but after I upload the new image it reverts back to the old one. What is the proper way to do this?

It should auto replace. I just tested on my test forum.
Might be a browser/cache issue.

Thanks, it was the cache, i cleared it and it works fine now. I'll have to try and remember that the next time.