Vista? That must be the worst o/s that M$ produced, or maybe ME was. Anyway consider Win7 as an upgrade. For Vista (and Win7 & 8) disable UAC, do not install in the default folder (C:\Progam Files(32)\blah blah), run REGACC.EXE As Administrator (right click the exe and select Run As Administrator). Also temporarily disable AV to see if that is the problem. BTW AV is responsible for many problems if it is not disabled BEFORE installing Sage 300.
Thank Ettienne Schwagele. I have just tried again that turn off UAC, run "regacc.exe" as an administrator. I don't turn-off AV. No luck.
Wish more suggestions for this problem.
Don't use Vista.
The issue disappeared after I uninstall it then re-install it.
*Community Hub is the new name for Sage City