If LM_LICENSE_FILE environment variable is set but the license manager insists that it cannot find the license file, check for commas in the LM_LICENSE_FILE variable list. This has even been known to crash FPGA Express and Project Manager.
Remove the commas, or replace with semi-colons if necessary.
The variable should read : LM_LICENSE_FILE=license1.dat;license2.dat;license3.dat
It should not under any circumstances contain any commas.