Not a TortoiseHg program problem, but anyway it is a problem with the project. I'm using TortoiseHG 4.0.1 on windows.
The link from the about dialog of TortoiseHG workbench points to http://tortoisehg.org, but the ulr of the project is not working anymore. When i try to access http://tortoisehg.org it redirects me to https://bitbucket.org/ When i try to open http://tortoisehg.bitbucket.org/ it also redirects me to https://bitbucket.org/
I don't see any mentioning or link of TortoiseHG on the bitbucket site.