Hi Junying,
You may have a compatibility problem with Structural Synchronizer and ProSteel. You should try installing an older version of Synchronizer and see if it fixes the problem. It would be better yet if you could upgrade to the newest ProStructures version.
You may have a compatibility problem with Structural Synchronizer and ProSteel. You should try installing an older version of Synchronizer and see if it fixes the problem. It would be better yet if you could upgrade to the newest ProStructures version.