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AR# 31184

10.1 ChipScope Pro iBERT - "ERROR:NgdBuild:32 - Cannot open input file ".ucf". "


When I attempt to generate an iBERT design, ChipScope Pro errors out and I see the following in the ibert.log file:

"Reading NGO file "<file_path>/<file_name>.ngc" ...

ERROR:NgdBuild:32 - Cannot open input file "ibert_top.ucf". Please make sure that the file exists and that you have read permission for it. This message may also occur if you are currently having network problems."


The issue is that the .ucf file has not been created by iBERT. This problem has been fixed in the latest 10.1 Service Pack, available at:

The first service pack containing the fix is 10.1 Service Pack 2 .

AR# 31184
Date Created 06/17/2008
Last Updated 12/15/2012
Status Active
Type General Article