Suddenly, I cannot open documents from Adobe Scan in Adobe. In Adobe Scan, when I tap on "open in Acrobat" or on the symbol the Acrobat app opens and then an error message pops up "unable to open document" and "an unknown error has occurred". I tried rebooting but am having the same issue. I have the free version of Adobe.
If you are still experiencing this issue, would you try opening those files on your computer browser using Documentcloud.acrobat.com and check those scanned documents. Make sure you login with the same Adobe ID which you have on apps.
If you still have trouble, you can share the file with us using private message while going on my profile and choose message. Also, help us with the screenshots of the error.