I'm not familiar with any URLs requiring a backslash. Could you describe that scenario in more detail?

It's a site to access an organizational email site... www.outlook.com\*****.org I don't normally use outlook or explorer although the same problem happens with them. I haven't seen the "\" used in a long time either, until the organization changed things around.

I would try changing the backslash to a regular slash, or check whether they have updated the URL since they distributed it the first time.

Forward slash won't work...that's what Firefox kept trying to change it to in the beginning...and the address is only 3 weeks old! Oh, well. Thanks for your effort and suggestions. Guess I'll just live with it.

Can't you navigate from the login page (e.g. live.login.com) to the desired page and create a new bookmark?

That is the usual way to proceed if a bookmark is no longer working due to changes made on a server.

I have a new thought. Windows sometimes has you preface your username with a domain. For example, let's say your Windows domain is mycompany and your username is jeff. You might enter your username on a Windows login screen as mycompany\jeff. This helps distinguish this jeff from the jeff that might be a local user or if you have a multi-domain environment, a jeff in a different domain.

Is that what's happening in this URL? In that case, try replacing the \ with %5C (%5C is the URL encoded form for \).