Similar random issues were experienced when attempting to set values in combo boxes using Windows 7 guests on a VWare host. The issues could not intentionally be reproduced and eventually disappeared after upgrading the VMWare server hardware. Two major differences is that we're testing Java SWT desktop applications and TestComplete aliases are not used. There's lots of moving pieces in software testing including monthly patch cycles, software upgrades, network changes and hardware upgrades, so it's not for certain that old slow hardware was the problem, but it appears to be. Currently, the virtual machines are configured as Windows 7, SP1, Dual 2.80 Intel Xeon processors.
