Thanks for the details, @perfect_connoisseur1351
Please check if there are any pending updates related to the OS, download and install all the mandatory updates of the operating system, and restart the computer.
Try saving a later file (the one that would normally fail) to a brand-new plain folder like C:\Test, not Documents or Desktop. If that saves when Documents/Desktop does not, folder protection is the cause.
Allow Acrobat through it: Windows Security > Virus & threat protection > Manage settings > Controlled folder access > Allow an app through Controlled folder access > Add an allowed app > Recently blocked apps > add Acrobat.exe. If you run third-party antivirus, add Acrobat as an exception (or briefly turn off the AV) and retest.
Also, reset the Acrobat’s Preferences, and repair the installation as shared earlier.
Then perform a clean installation if the issue persists. Please download the Acrobat Cleaner tool, remove the installed app, and restart the computer. Then download and install Acrobat.
Please try these steps, and let us know how it goes.
Regards,
Anand Sri.