We have a file imagename.txt with a simple key of:
imagename=foo.tar

The file imagename.txt does not exist as see in the log output below but it still runs anyway.

 
14:08:56  [parameterizedtrigger] Could not trigger downstream project, as properties fileimagename.txt did not exist.
14:08:56  Triggering a new build of foojob_nightly #1205

Also, not sure why it displays fileimagename.txt over imagename.txt