To dismiss the error message, click No. There is no ill effect to this error.
This problem is scheduled to be fixed in the EDK 12.2 software. Meanwhile, download the "
tabs.zip" file and unzip it to the following directory:
< XILINX_EDK >\doc\usenglish\xilinx_template_files\documentation_locator_files\
This issue has been fixed in 12.2.