Whenever i get a skin for MSN Messenger, MSN messes up and wont open at all as in itll lo on automatically after downloading but after that it wont open from the taskbar...
Are you sure that the skin you downloaded is for the right version of MSN Messenger, check that you are using the version of MSN Messenger that goes with the skin first... The installation may have also gone wrong...
Try uninstalling MSN Messenger from your computer completely, including deleting the "MSN Messenger" folder from C:/Program Files/, then download the latest version from http://messenger.msn.com. Then of course, download a 7.5 skin from www.messengerstuff.com.