After installing ISE 9.1i Service Pack 3, the following error occurs when opening Project Navigator:
"ERROR:PersonalityModule:7 - Unable to open Xilinx data file for Vendor/Device Module "spartan3a". Please make sure that it has been correctly installed before continuing. INTERNAL_ERROR:PersonalityModule:baspmspec.c:1698:1.71 - Could not load definition file <spartan3a.acd>"
This is an error caused by files added with Service Pack 3.
To fix the issue, you must delete the following files from your Xilinx ISE installation: