Files and folders turned into exec files

Any files created on a modern Mac should have an extension. If you've got old files created before extensions on the Mac became standard, the Mac metadata that identifies what the file is will be lost any time that file is transferred to a Windows file system.

oy wrote:

I've not been connected to any Windows PC, only the Microsoft OneDrive cloud service, where is when I first saw this happen.

If the affected files are all on OneDrive, my guess is that they were accessed at some point from an infected Windows PC.

The files look exactly like the one you show, and as they were folders, they have the same name as the original folders, with no extension.

Did you check for an extension using Get Info? If not, you need to do that, as extensions may be hidden in the Finder, but will always be visible there.

If they really truly had no extension, and if some of the affected files had never been on Microsoft OneDrive, that may be a sign of disk corruption, and the initial association with OneDrive was simply coincidence.

I have the same problem. All files affected appear to be at least pfd files that had no extensions when originally saved. This is probably the cause of all (hundreds) of initial warnings when my stuff was uploaded to OneDrive. SO every time I open a pfd, I have to manually add the extension to it.

Such a Windows-esque quirk: extensions should always visible in file names. So I guess the way OneDrive stores data is on millions on floppy disks in the "cloud."

Do these files you're seeing have a particular extension? Select one and choose Get Info from the File menu, then look at the Name & Extension info.

If a file doesn't have an extension at all, it will be displayed with an icon like this:

That doesn't mean it's actually an executable file, but the Finder doesn't know what it is. In such a case, you need to give the file the proper extension for the type of file that it is.

If you're seeing files and folders replaced by files with a .exe or .lnk extension, those files/folders have been exposed to a Windows PC that is infected with malware. In the case of a flash drive, it has been connected to an infected Windows PC. If you're seeing files on your Mac hard drive showing this behavior, they either got copied or synced from an infected Windows machine, or you have some kind of file sharing that allows an infected Windows PC to access and modify files on your Mac.

In the case of .lnk files, the originals have probably been hidden elsewhere on the disk and are intact. Try showing hidden files and looking for the missing items in a hidden folder on the drive in question. Note that there are normally quite a few hidden folders/files on the main drive with your system, and there are always some hidden items on external drives as well. Do not mess with those if they aren't obviously a repository for the missing files!

If the extension is something like .exe, there's probably no easy solution. Those files/folders may have been encrypted (if the Windows PC was infected with ransomware).

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