.XISE File Extension
What is a XISE file?
Project file created by ISE, an application used for designing computer hardware electronics devices; saves a list of the source files used by the project as well as project properties and the software version for the project; used for FPGA (Field-programmable Gate Array) design.
NOTE: The ".xise" extension was introduced with ISE version 11 software. Versions 7 through 10 use the .ISE extension, and ISE 5 and 6 use the .NPL extension.