AMD Athlon™ 64 X2 Dual Core Processor Driver for Windows XP and Windows Server 2003 Version (exe) 1.2.2
You should be downloading and running an executable named amdcpu.exe.
Workaround If the above solution doesn't work, you may need to apply an affinity mask to NEOPro.exe and W32MKDE.EXE.
ctrl, alt, del to the task manager
under the Processes tab, find the NEOPro.exe
right click on the process and select the "affinity" option
if you do not see "affinity" in the dropdown, you will not have dual core processors and this will not be the issue.
if you do see "affinity" in the dropdown, select it and make sure only one CPU core is checked
again, under the Processes tab, find the W32MKDE.exe
right click on the process and select the "affinity" option.
make sure only the same CPU core is checked
go into NEO and synchronize the message store
if problems still persist, try setting the affinity for both processes to the other core.
The issue with this workaround is that it needs to be applied whenever NEO is opened. Our experience is that the AMD fix works for AMD Dual core processors and so the workaround will probably not be necessary.