In my previous post (LinkManager – Working with URL’s in Sitecore 6) I was quite enthusiastic about the addAspxExtension feature, which allows you to disable the .aspx extension in Sitecore URL’s, as long as you provide an 404 handler or use IIS7.
Unfortunately the feature seemes to affect the Sitecore Client negatively, because when enabling it, it is no longer possible to edit Sitecore contents:
The problem was found using a Sitecore 6.0.0 rev. 081222 running on a IIS6. If you are running this version of Sitecore, you should not set the addAspxExtension to false if your site requires the Sitecore editor to work. If your installation is a front-end server only, you should have no problems.