Board Thread:Support Requests - Getting Technical/@comment-1738746-20150729064900

I haven't found any information on this anywhere, but it's something that is occuring frequently now on a wiki I admin. Certain files just seem to become "corrupted"- no one replaces or touches the file yet over time, the file seems to blow up in size and pixelate the image as a result.

Example of 'corrupt' file:

Example of non-corrupt file:

If you look at the two in their small size closely, you can see the corrupted one is kinda blurry- this is the result of it having become this blown-up version. Despite the message saying "No higher resolution available" for the corrupted file, if you click on it to view the image itself, you'll see it goes to a blown up version whereas the non-corrupted file doesn't.

When these files were both originally uploaded, none of them had this issue. At some point over time, certain files changed to this without anyone doing anything to them. I thought at first it might be something to do with file redirects but the non-corrupted files have redirects too so it wasn't that. This is occurring on dozens of files at random across the wiki, though all of them have been happening to sprite images. Has anyone ever seen something like this before and how can I resolve it?? It's becoming a huge pain to go around replacing the files to make them normal again only for them to revert back to this corrupted state at some point again later on down the track, especially as some files are extremely difficult to get in the first place. Any help at all will be hugely appreciated!! 