[FIX] Illustrator 2020 (24.0, 24.0.1) crash a few seconds after startup in Windows 10

After updating to Illustrator 2020 and editing a few files, I used it again a few days later and found that Illustrator crashes (launches the crash report window) a few seconds after launching, whether opening an existing file or launching Illustrator from the Start menu. 2019 still worked fine.

Removing "AppData/Roaming/Adobe/Adobe Illustrator 24 Settings" did nothing to fix the problem, and neither did updating my graphics drivers to the latest version.

What did help was unplugging my Ethernet cable (no WiFi either). With no internet connecion, Illustrator launches fine and stayed open for at least a few minutes of testing. After plugging the Ethernet cable back in, I added a firewall rule to block Illustrator.exe's outbound network connections. This seems to have solved the problem.

So for anyone who has this same issue, try disconnecting from all networks and see if Illustrator now launches. If it does, connect back to your networks and add a firewall rule to block Illustrator's outbound connections.