I've downloaded some of my site, to transfer it to a new site, however when I upload it to the new site, I've found that if I zip it all up, it complains that the headers have already been written when I view the site, however if I just straight upload it, I don't get the error.

I don't think it's a coding error, think it's something to do with the upload\download. Anybody any ideas?

I guess that during the encodation of the zips under PHP or whatever the engine writes a space, a carriage-return, a line-feed or any other ASCII-character that normally doesn't cause any problems. Now when PHP executes it, the engine thinks the HTML-code begins, sends the HTTP headers and then stucks when it comes to modify the header.

That's my only explaination I can think of. But it's quite interesting to know what really is the problem.