I just upgraded my PC with two tadeonal memory sticks and now get an invalid license message when trying to start the program. I tried using the popup reregistration and it returns a server error message. I have messaged the admin for pilot2atc, but have received no reply. Any suggestions on what I can try next?

you must wait for Dave 

Make sure that P2A has permission to access the internet.

The latest version of P2A lets you deactivate and activate your license key.  After you install version 2.6.2.3R2, just:

• ·         press the Register button (if it opens in trial mode)
• ·         enter your email and the license key (be sure to use the email you purchased with, like your PayPal email)
• ·         press the Deactivate  button
• ·         after that succeeds, press the Activate button

 That should get you going again.

If you get an error message, please send a screenshot of it to [email protected] so I can see what’s wrong.