My computer started acting up today. The first indication that something was wrong was when POP mail requests started throwing strange error codes (SMTP and Exchange mail worked, just POP was failing). And then FTP transfers started retry lots of random packets. The only change I made to my computer was installing Communication Manager, the software for my new 3G card, but that could not be the problem, the card was not in the machine and Communication Manager was not running. Right? Well, after lots of tinkering I uninstalled Communication Manager, and suddenly everything started working again. Which is bizarre, because Communication Manager does not startup by default, it is run only when needed. Just to prove the point, I reinstalled and uninstalled Communication Manager several times, and sure enough, when installed (even if not running and without the PC card in the machine) lots of stuff broke (including POP e-mail), and when uninstalled the problems went away.
After lots of Google searches and a long chat with a techie at Cingular, the culprit was identified. Communication Manager installs another application, a data acceleration client. The software improves connection performance by doing things like degrading image quality, and I assume that there is software on the Cingular network end that actually does the compression as requested by the client. Lots of Communication Manager users have reported issues with data acceleration with all sorts of applications (including Norton Anti-Virus and Norton Internet Security).
But still, how could software that is not running cause problems? As per the documentation:
Data compression is only in effect when Cingular Communication Manager is connected to a Cingular GSM network and has successfully negotiated a session with the data acceleration server in the Cingular network.
In other words, if Communication Manager is not running then neither is data acceleration. And even if Communication Manager is running, data acceleration only impacts connections via the GPRS/3G card, not any other connections. That’s what the documentation implies.
And, apparently that is not true. The Setting dialog in Communication Manager allows data acceleration to be started stopped and configured at will, and also allows it to be installed and uninstalled. Well, I uninstalled it. And suddenly everything works again.
Honestly, I am appalled. For starters, why the heck would data acceleration be tinkering with POP packets? And why was it messing with data sent over regular LAN and WiFi connections? But the bigger issue is simply this, how dare Cingular install software telling me that it will only run when executed, when it was clearly running at other times, too?
Not cool at all. No, I won’t dump my 3G card yet, I still need to give it a real world road test. But if any of you install Communication Manager, do yourself a favor and uninstall data acceleration!