This is not a "normal" problem - it's just too weird.
The first step should be to do a deep anti-virus scan on the computer.
I see that you have Avast, so use it first, then download and use
If no viruses were detected, run sfc /scannow.
If the sfc scan found no errors,
to find out if some installed product is responsible for this problem,
restore the fonts and reboot in Safe mode.
If the files have disappeared again, then this is a Windows problem.
Otherwise if the files are still there, then some installed product is causing this.
if the problem is caused by an installed product, first use Avast to do
a boot-time scan.
If Avast finds nothing, use Autoruns
to turn off startup programs in bunches until you find the one causing this.
Each time restore the fonts and reboot again to check.
Once you find the product causing this, restore startup programs using Autoruns.
For the case where Windows destroyed its own font data, you could :
- Get the contents of
C:\Windows\Fonts from another PC
- Copy these fonts into a temporary folder
- Use regedit to delete (after saving) the contents of
- Copy the fonts into
- Re-install the fonts by opening Control Panel / Fonts
- From the File menu select 'Install New Fonts...' and add the fonts
from the temporary folder.