I tried restarting my computer, which, of course, didn't work. I tried unleashing the full force of all my virus and malware scanners, to no avail. Finally, I broke down and called Adobe support. I'll give it to the guy who tried to help me, he must've gone through every solution in his manual. Even so, I was on the phone for over two hours, only to have it end with "It's not a problem with our product, it's a problem with your .NET Framework." How did we figure that out? By doing something we could have done in the first five minutes of the call, instead of the last, but the tech support manual told him not to tell me to do. So you don't have to wait on the phone for hours and miss days of productivity, here's a quick and easy way to determine if your problem is the .NET Framework and how to fix it in about 10 minutes.
All instructions are based on a Windows 7 environment.
Determine if your .NET Framework is the problem
If .NET really is your problem, you will probably have other symptoms besides Adobe products not working. You may notice Internet Explorer acting sluggish, or other .NET programs, such as Windows Live Messenger, not working properly.
You can also do these quick steps:
1) Go to your Control Panel
2) Click on "Administrative Tools"
3) Click on "Services"
4) Scroll down to "Flexnet Licensing Service" and double-click. You will see this window:
My Flexnet service is running because it's fixed now, if your Flexnet service is not running it will say "Stopped" under "Service status" and you will be able to click the "Start" button. Your "Startup type" option may also be set to manual.
5) Click the "Start" button.
6) If you get an error something to the effect of "Cannot start because blah blah blah didn't respond in a timely fashion" or "Cannot start because access denied" you probably have a .NET issue. Congratulations! This should be easy to fix!
Fix your .NET issue
This is face-palmingly easy, especially considering I labored for two days trying to fix this before figuring this out. Googling "fix .NET framework" gives you all kind of weird techno-babble about typing long command sequences into cmd and playing with the registry. Bah!
2) Download "dotnetfx.exe"
3a) If you get an error saying "This program may have installed incorrectly" click "Reinstall with recommended settings" and reinstall.
4) Get back to work!
Hopefully I've saved some people a couple of days of agony, or at least a couple of hours on the phone.