I've recently been getting kicked for "ignoring MD5Tool Queries" from every server. This has only been like that since a PB update which hasn't been fixed yet.
Some servers have also been crashing, but I believe there's an update for that now.
Anyway, I've been searching to fix this problem, and finally found a solution on the AAO Tracker Forums. You actually have to follow the following steps.Tuesday 12.11.2007 [2:15PM]
Version 1.620 of the PB Server for AA has been released to our PB Master Servers for auto-update and to our website download page. This version addresses a crash issue on some servers.
1. Uninstall America's Army
2. Delete the remaining America's Army folder and it's contents
3. Reboot
4. Install America's Army + relevant patches
5. Run a manual, out of game, PB update (America's Army->System->PB Installer)
6. Optimize AA using Deano's guide http://203.88.118.161/~nathum/ADFTEAM/m ... pic&t=2443
7. Do the registered name thing by opening the console (press `) and then typing in the code which can be found here http://203.88.118.161/~nathum/ADFTEAM/m ... topic&t=89
8. Have fun and play
This has so far worked for me, I only got kicked once because I actually forgot to do the registered name. Also, if you tweak AA, you cannot minimize AA/not play in full screen mode. This will cause AA to crash. It didn't crash for me per se, but it did kick me from game for MD5Tool.
Hope this helps. A few of you might be having this problem, I know Denis said he was.
Fox out.