I have noticed that calling out from the Call History section of UCA is inconsistent. I think I see the pattern. I am running version 6.0.220.0 on Win 7 x64
If I double click on Missed Calls (red handset) it works.
If I double click on Received Calls (blue handset) it works.
If I double click on Dialed Calls (green handset) UCA throws up an error saying it was unable to dial 5555551212 or whatever number you had.
Anyone know if this is fixable?