We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 31600

10.1 Schematic Editor - "Error : Symbol Not Found" when using User Libraries


Schematic design contains custom symbols from a User Library. Attempting to synthesize the design returns:

"ERROR: Symbol Not Found"

How do I resolve this issue?


The issue is with the registry location used to locate user libraries.

To work around this issue, copy the ECS registry in ISE 10.1 to paths with 10.1i. To do this:

1. Go to Start -> Run.
2. Type regedit and press Enter.
3. Go to the following key: HKEY_CURRENT_USER\Software\Xilinx\ISE\10.1\ECS
4. Right-click and choose Export.
5. Save the file.
6. Open the .reg file in a text editor.
7. Replace "10.1" with "10.1i" (use the text editor's Replace Functionality).
8. Save the file.
9. Go back to the Registry Editor and select File -> Import.
10. Select the file saved above.

Run Synthesis on the design; the User Libraries should be read correctly.

This problem will be fixed in ISE 10.1 Service Pack 3.
AR# 31600
Date Created 09/04/2008
Last Updated 12/15/2012
Status Active
Type General Article