I have been for other clients and intended to for this one. I have other clients who own U.S. LLCs and have no income so I've only been filing 5472 with 1120. For another client I also did the 1040 NR with 8833 and Schedule OI to claim treaty exemption but they needed an ITIN so I mailed all of that along with W-7 and the ITIN was granted. Since this customer already has an ITIN, I was trying to file electronically and ran into this issue. I prefer to e-file rather than mail so I can get the e-filing confirmation.