You need to manually switch off frequency when this happens then switch back in the ATC box. So go to your radio panel and in COM1 switch it to a frequency other than the current one, then you'll get the contact frequency message in the ATC box, select that, and you should be in business. It doesn't stop it from happening again during the flight, but you can do the same thing to get it back!!

Just to be sure you have the correct check marks set, FSX saysBy default, Flight Simulator opens the ATC window automatically when messages are sent or when a response is required from the pilot. Some pilots prefer that the ATC window remain hidden until they want to open it manually; others want it to appear automatically.To have the ATC window appear automaticallyIn the General Settings dialog box, select the Auto-open ATC Window check box. Click OK. If no txt shows in the ATC window when it opens you might want to check your keyboard.I have tested several different type keyboards on the many different computers I run FS9/FSX on and they do make a difference.Some of the wireless keyboards I have tested do not always function properly when FSX is running. Before you consider a reinstall of FSX, I would use another simple type USB or PS2 type keyboard as a test if by chance you are using one of the more exotic wireless types (USB mini-receivers).

As suggested above, I just switch the radio freq.Then the ATC window has an option to switch back to the center you were talking to. In the LDS 767 I just hit the transfer button.I thought I was the only one having this problem.

Wow, just wow. The more I read the sorrier I am that I bought FSX for my next computer. http://smilies.vidahost.com/otn/sad/nosmile.gif

I had the same problem of a blank ATC screen. It went away when I reverted to the default ATC auto-open setting. Really annoying that it is not possible to hide the ATC text.Cheers,N.