Errors when trying to copy a new banner?

Using a Digi ConnectPort LTS16, firmware 82002228 Rev K

I using a browser I enable the login banner in the system configuration. Open a console window with putty and run the following commands:
>bash
>vi /usr2/issue.net

I hit ‘i’ to insert text, copy the new banner into the clipboard from a text file, go back to the console window and right click to paste the new banner into the vi file…Sometimes the console window becomes unresponsive, I’ve had blue screen of death. I always get a ‘last modifying cmd overrun’ error. Sometimes it will paste part of the banner in or paste the banner and then append the old banner. It’s never clean. Anyone else have this issue or know how to solve it?