I was noticing all the URLs within my site only had one slash after 'http:/' - my browser (Safari) doesn't seem to care, but everything automated does. For example, you can't share a link with one slash after the 'http' on Facebook or Digg (you'll get an error).
The first place I looked to resolve this problem is Settings > General for the blog itself. Here I was shocked to find that the blog URL had a hardcoded prefix of "http:///" three slashes. See this screenshot: http://yfrog.com/32afsp
How can I fix this?
For reference, my blog URL is http://fastfoodnyc.com - You'll notice every internal URL reads http:/fastfoodnyc.com/whatever (one slash after the "http:")
MT Version 5.01.
Reported on Movable Type 5

Hi Kai,
The fix is as simple as changing the blog URL from 3 slashes into just 2 ;)
Do it inside:
Settings -> General
Happy blogging,
Mihai Bocsaru
Hi Mihai,
The problem was I couldn't edit the beginning of the blog URL. In settings it looked like this:
http:///>
> being the text edit field.
I just found the problem: The site URL (a concept introduced in MT5) was simply "http:///" because I wasn't using it. I had to change this to my blog URL.
Problem then was that I couldn't just leave the blog URL blank, it wanted something after the site URL. I fixed this by manually editing the DB value.
The site / blog relationship in MT5 can become a little confusing. At least all is well now!
Sorry but there is a bug that you cannot leave the blog URL blank. The fix itself has been made and will be included at the next MT5.x release.
http://bugs.movabletype.org/default.asp?103496
Today i upgraded to MT5. It's late night here and my site is corrupted because of this "http:///"
In settings, where you define url of the blog/site and root, url starts with "http:///" that is hardcoded into the page. I can only type the url but not edit "http:///"
Then it happens that the site is generate with "http:///" links in the site: css, images, links etc. are like "http:///www.domain.com"
I did a search using notepad+++ in mt5 whole folder and subfolders, looking for "http:///" to fix it. Nothing.
Then i searched in mysql via phpmyadmin. I only find vlaues containing "http:///"
How do i fix it? I have other sites on this MT5 and i am scred to even touch them!
Kai, how did you fix this?
Hi Vito,
What is your Website URL ( not a Blog URL ) ?
It seems that it has been changed to be blank.
You can confirm it by selecting a "website" from the navigation,
and select "Settings - General".
"Website URL" has to be filled with a valid domain though you can leave "Blog URL" to be blank.
This documentation might help to understand the concept.
http://www.movabletype.org/documentation/administrator/managing-websites/index.html
Thank's a lot for the answer, that's exactly what i was looking for