A separate cache is stored to allow Xilinx applications to use changes in the environment without needing to reload the application. To clear this cache do the following:
1) Go to your %HOMEDRIVE%/.Xilinx folder.
2) Delete the license_info.cache file.
On Windows systems, the following procedure can be used:
1) Start -> Run... and type 'regedit'
2) Navigate to HKEY_CURRENT_USER -> Software -> FLEXlm License Manager
3) Edit/Delete the key for XILINXD_LICENSE_FILE/LM_LICENSE_FILE such that the old server is no longer referenced.