VB6 app hangs for a while on Windows Server 2008 sp1

I have a problem with our VB6 app. It's an old system with lots of forms run on our customers T开发者_运维技巧erminal Servers. One customer has a problem and they have two Windows Server 2008 (32 bit), I don't know of anyone else with the same problem. Other customers has XP, Win7, Windows Server 2003 and Windows Server 2008 (64 bit). I haven't found another Windows Server 2008 (32 bit) yet.

The problem is that after clicking the OK button in a small subformand there by closing it, the parent form is unresponsive for 1-4 minutes. This happens most of the time but I haven't found a pattern. When you click the OK button, it does a small SQL INSERT via ODBC in an Access Database. After that the subform is unloaded. The subform consists of a couple of textboxes and a button. There are no problems with larger subforms with way more controls.

I've tried logging but the timespan between the start of the click event and closing of the subform and returning to the main form is under 10 seconds. Still the mainform hangs and is "Not responding" for minutes.

I can add that the mainform is a subform to another large form but these two doesn't cause a problem, just the small subform.

I would be more than happy if someone could suggest something I could try.

I'd throw ProcMon at it and see what registry keys and files are being hit when you run this subroutine.