Ross,
Yes, now I can confirm we did follow ALL the steps on http://support.microsoft.com/kb/2009942 and still experiencing the issue. As you was saying - the "unknown error" issue, this is a result of timing - you move/delete the item and within the same second (or two) before the folder view refreshes and you're welcome to explain it to our users. They didn't experience it on the Outlook2003/Exchange2003 and now we moved to better, faster system and they getting this error. Why this refreshing timing happening?
We eventually will move to Outlook 2003 and I would like to upgrade all our client's workstations with it but as you understand you cannot do it overnight. Migration process takes some time and we are 2-3 month away from it. So, is it mean we don't have any solution here? Please clarify.
Thank you in advance and I understand you working hard on this but still - this is a big issue for us and a lot of other companies.