Unable to e-file due to TurboTax internal error : Your Transmission Didn't Go Through "Unable to locate the attachment at /attachment/ Form8949ExceptionReportingStatement-1.pdf. Please go back and re-attach it

[sue2278]

I had the same error for 8453 attachment. I tried creating a new file, renamed the file, changed JPEG to PDF to PNG. Nothing worked.

Then, before I hit the Transmitting button, I tried "TOOL" option on the left top menu, "ATTACHMENT", then click on the Attached files to see if they are opened. The files I have attached did not open somehow. 

Then, I saved the file in the different folder in my C-Drive, NOT ON DESKTOP, and tried attaching to 8453 again. Then it works! 

I think it has to do with converting the file to PDF when I upload my file from the DESKTOP. Try saving the file somewhere else, then try uploading. Hope this helps!