I was unable to e-file a 1040-NR with a pdf attachment listed as "Other". The Error Detail Reads:  This submission contains a form or schedule which MeF is not accepting as a binary attachment. The form or schedule must be submitted in XML format instead. In this case, a refund was being requested for 8288-A withholding. The worksheet was completed properly. I attached a copy of the 8288-A as a pdf scan and listed it under "Other". 

Pro Series only allows attachment of files with pdf format in the 1040NR return. I cannot even find an XML file if I wanted to attach it using the ProSeries search function in uploading attachments. I've never had this problem with 1040 Returns. 

Is it even possible to e-file a 1040NR return using ProSeries with a pdf file attached? All of my other 1040NRs require paper filing because 1042-S withholding does not permit e-filing or because treaty exemption Article Numbers are not accepted by the e-file system.