ID:267006 Signal "<name>" does not exist in SignalTap II File

CAUSE: In the trigger condition expression or signal view section of the current SignalTap II File (.stp), you referenced the specified signal or bus that does not exist in the signal set. You manually edited the STP File, but the file is invalid.

ACTION: Remove the signal or bus from the STP File. If the file is supplied by a third-party tool vendor, contact the vendor. To avoid this message in the future, Altera recommends using the SignalTap II window to modify STP Files, rather than editing the files manually.