Microsoft has issued a fix for this problem below, but this did not resolve the problem for myself.

Go into Registry Editor (Start, Run, “regedit”). Go to HKEY_LOCAL_MACHINE, Software, Microsoft, Office, 11.0, Delivery. There should be only 1 directory under Delivery, which is your DownloadCode (mine was 90000409-6000-11D3-8CFE-0150048383C9). Select that directory. On the right side of the screen, right-click on CDCache. Change the value to 0.

I was getting this error in relation with outlook 2003; I have yet been unable to find a resolution other than re-install at the moment I would appreciate anyone that has got a fix for this to email me.