chaitanya

For some reason as of this morning I can no longer run .msi (microsoft installation) files. Double clicking on the msi file results in the "Opens with.." window popping up as if the system does not recognise the msi extension. A check of the Windows Installer service shows that it is not running and any attempt to start it results in the 997 error occuring. Any one have any ideas where to start looking to solve this?