When I edit a blog by signing in on the front end of Joomla, I click SAVE afterwards, and the screen goes back to the home page (where the login form is) but the blog entry disappears. If I look into the back end I see that it has been unpublished. Any idea what's going on?

Do you get any errors either on page or javascript errors through the console of your browser?

No, no errors like that are showing.

On a different computer I find that after I edit the text and click save, the program saves it, which is good, but it changes the selection YES to NO for publishing. Even if I reclick on YES, it won't stay. I end up closing, and of course, the new entry is gone. I can find it in the backend as an item, and can click to publish it there.

When I look at Module Manager and choose K2 Content (which is enabled) I see that it is not set to appear on the blog page. What does this mean? Should it be?

Do you load any third party extensions or content plugins that might be responsible for this issue. Could you please Disable them one by one and check again?

Thank you.