why do I get this error in FP?

[byepolar]

I have to delete the folder in question and re-publish when this happens:

The file 'folder/index.html' in the Web 'URL' has been modified 3/15/2003 12:09:06 PM by 'byepolar'. Are you sure you want to replace it?

I click yes, at end of publishing it says:

Server error: The page testimonials/index.html has been modified by byepolar on 15 Mar 2003 10:54:26 -0800

[oilman]

what happens if you click no?