Excel slowness

Hi,

I have an Excel worksheet with several formulas and add-ins. I have some problems when changing cell values - modifications being slow.

I think it's down to a couple of Add-ins (Bloomberg and Thomson). When I remove the add-ins the worksheet modifications seem much quicker, the problem is that I need access to the add-ins as they link to external databases.

Is there a debug mode in Excel where you can step through the calculation process? Or test the network connection within Excel?

Thx