I GOT IT (I think)
I had a some old stuff from a previous WP blog in the htaccess file (which I was changing just as I bet you were looking at it).
Instead of overwriting it, I posted the new Multisite info under it. (Now it is overwritten).
Thanks for the help! – Cindy
Thanky-you, but I already checked the error log in cpanel.
It shows no errors. I also recreated the error to see if the log would pick it up, but it’s still empty….
SOMETHING I didn’t notice before, not only do I get the message when I try to go to the subdomains, but I also get the message when I click on any of the links on the main blog page. Only the home page and the wp-admin work, the ABOUT, posting page etc. give me the message….