The problem with file associations is quite well-known, and the 'new method' does nothing to alleviate it, to my knowledge. It actually can interfere with the Windows 7 method of extension management, and result in the 'matlab opens but does not open my m-file'-problem.
The problem usually disappears by uninstalling, deleting the file associations through the registry or an utility, and reinstalling. Messing with the registry can be quite dangerous, but if someone follows the instructions, there is no danger of damage to any system or program. Same goes for utilities.
"Wayne" wrote in message <email@example.com>... > DO NOT manually delete registry settings nor use fileassoc! > > In R2010b, a new method for registering file associations was introduced. It allows multiple installed versions of MATLAB to have their own file associations (i.e. no more m-file progid). This allows you to easily switch your file associations from one version of MATLAB to another. To avoid the problem below, uninstall the pre-R2010b version of MATLAB before installing any of these newer versions. If you?ve already screwed things up, then reinstall the new version. These newer versions can be installed or uninstalled in any order. >