Thread:Project:Support desk/Sanitizer.php not uploading

I'm a bit confused by this, and I apologize if it might be a GoDaddy/Filezilla question more than a Mediawiki question.

I've uploaded the entire package to a folder in my godaddy Linux shared hosting account, with PHP 5.4.x / MySQL 5. I get the entry page popping up, telling me to set up my wiki, then the next page gives me the following error:

Fatal error: require: Failed opening required '/wiki/includes/Sanitizer.php'

And the thing is, it's right. I didn't get any errors from Filezilla, but Sanitizer.php did not upload with the rest of the files. Not only that, but I can't upload it on its own -- no errors, and I can see that it uploads, then it's immediately deleted.

Any ideas why this might be happening? I've tried renaming the file, uploading it to different locations on the server, etc, but still can't get it to stick -- I see it appear on the server side file list, then it disappears.