I searched the forums but didn't see anything on this issue, so I thought I'd post a quick note (apologies if this is well known).
If you're having problems installing the desktop software bundled with your 8830 (or if you download the install package from the web), try the following MS patch: Download details: Windows Script 5.6 for Windows XP and Windows 2000
It is an update to the XP Windows Scripting library which the RIM software's installation package is built on.
I spent a few hours trying to figure this out but the above kb article & patch took care of it for me.
And on a side note, I love this phone. It's a world of difference from my 7250!