This solution applies if you cannot open fonts in Windows when the fonts are are located outside of the %windir%/fonts/ directory, or if Adobe Photoshop and Illustrator are giving the following error in regards to ADMUI3.fon:
$$$/ADMDialog/iFontProblemWarming=The Adobe UI font could not be loaded.
The solution is as follows:
Press windows key + R simultaneously to open up Run menu, enter services.msc, navigate to and enable the Windows Firewall service. Also set it to automatic start.