Using Windows 10, WLM, and only recently have noticed some emails hang up in the outbox. I double checked the PDF files to be sure they were not corrupt or overly large, they were not. 162 kb., 2 files.  Nevertheless, I had trouble sending them out and I understand some programs have restrictions. I found no settings to indicate a way to change this. I use Rise Broadband and they have never had an attachment restriction, so I doubt that is it.

I also checked the Properties - then, Advanced settings box about breaking apart messages if over a certain size, but my box was not checked.  

Any ideas?

Lennia