ID:274003 Net "<name>" has multiple sources, but net should have only one source

CAUSE: The EDIF Input File (.edf) contains multiple sources for the specified net. Nets must have only one source. This problem may exist in the source design file. This message can also occur if you specify incorrect names for the VCC and GND signals that are used in files generated by an EDA design entry or synthesis tool.

ACTION: Make sure you specified correct names for the VCC and GND signals. If those settings are correct, try to correct the source design file so that the specified net has only one source. In general, it is better to correct only the source design file rather than the EDIF Input File. If you prefer to edit the EDIF Input File, make sure it conforms to the format for EDIF version 2 0 0. If necessary, consult your EDIF manual.