We just upgraded our BES from 4.1.x to 5.0 at the end of last week. My users are now saying they are getting an error when trying to do a wireless upgrade stating "Requesting new updates has been disabled by your administrator." I do not recall changing anything that would do this, and in fact in the Wireless Software Upgrades section I have everything explicitly set to allow. I'm not sure this is actually part of the IT policy since I have the same problem and I have a custom policy for myself, but I don't know where else to look.
Just wanted to update to check the "BlackBerry Device Software deployment managed by BlackBerry Administration Service" option under BAS. This needs to be set to "No", which will change some of your settings in the Wireless Software Upgrades tab in your IT Policy.