Transom wrote:

After installing phpsuexec, newly uploaded files are no longer accessible.

The first problem was that MediaWiki wouldn't upload files because it complained the files were corrupt or had bad extensions. That seemed to be a MIME detection issue and my sys admin set $wgMimeDetectorCommand to "file -bi" and that solved that problem. Now the files are being uploaded, but newly-uploaded image files are not visible in the wiki. On an Image: page, the image is not displayed and clicking the image link leads to an Apache error. The newly uploaded files have permissions=644 whereas before they had 755.

So---are the permissions wrong? I don't know why MediaWiki would need "execute" permissions for images, but when images are 755 it works, and when set to 640, it doesn't.

I guess it has to do with the read permission for everybody, and not with the execute permission. Can the files be read by the user under which apache runs?

ALSO... I have noticed that MediaWiki shows a link on the image page for images uploaded in the past, and the MIME type is displayed as "text/plain". Both issues lead me to believe there is a filetype/mime issue somewhere and it'[s probably related to something I didn't do right when configuring the system.

The mime type is stored in the database. As those images were detected as text/plain in the past, they're still listed as such. They would be correctly detected if you reuploaded them today.