error code 4960 when saving a .plist

I'm trying to create a .plist file in textwrangler, something I've never done before. I'm using these instructions which tells me to:

Save code as com.rTask.plist file under path ~/Library/LaunchAgents.

So I follow those directions and it gives me the 4960 error. Here are two screenshots to give a visiual:

I've done a pretty extensive Google search and still haven't been able to fix it. Can anyone help?

Solution 1:

You are trying to create a launch agent with:

1. the wrong extension (plis)
2. in the wrong folder (/Library/LaunchAgents/ (suggested by the visible plists: java oracle/microsoft? updater, google keystone and teamviewer))
3. with the wrong app (TextWrangler)

TextWrangler isn't compatible with macOS 10.13. Download BBEdit or another compatible editor and try it again ;-)!