Warning! Problem upgrading . Your server may not be able to connect to blogs running on it.
Error message: malformed
Warning! Problem upgrading . Your server may not be able to connect to blogs running on it.
Error message: malformed
This seems to get quite a few people, it looks like its something to do with the way it does the ugrades. There was a post on how to fix it the other day.
Alternatively you can simply go into the back end for the blog in question which will do the upgrade.
I also had the same problem and fixed it myself. It might help you.
Wordpress MU Site Upgrade Bug: Your server may not be able to connect to blogs running on it