While working on an flash CS3 project today I accidentally pasted a long phrase into the “font name” dropdown of the properties panel. this crashed flash and it would not boot up again properly – whenever I went to open any .fla file, I would get the Windows “Flash CS3 Has Stopped Working” message. After searching the web and even calling Adobe tech support, I took the last resort of digging through the registr. I found the culprit at:
computer\HKEY_USERS\[identity string of long numbers]\Software\Adobe\Flash9\TextFontPanel
The key “Font Name” was set to some long string with likely illegal characters. Changine it to a default of “_sans” allowed flash to boot normally. Hope this helps someone!