Adobe Acrobat No Longer Converts Files to PDF

Hello, I have seen other threads about this issue before, but I still cannot get Acrobat to behave properly. I have spent over 3 hours on the phone with Adobe support, and they were not at all helpful even after they tried everything via remote access. We do print work for customers, and they just send their file in whatever format they have. I have never ever had this issue my entire time using Acrobat, but NOTHING will convert to PDF. I get the same error message every time: 

"Adobe Acrobat could not open 'filename' because it is either not a supported file type, or because the file has been damaged"

We get this message no matter what. And I actually found *a* fix. I deleted the entire Acrobat folder from the Windows Registry Editor. This actually worked... for one file. After doing one file it would revert back to giving that error message. I thought maybe it had something weird to do with our main computer, so I tried it on all the other computers and they all do the same thing whether the file is downloaded from an email or created locally on the machine. All the computers we tried on are Windows 10, and Acrobat is up to date on each one. If any of you could help that would be greatly appreciated!