Messenger stopped working on Windows 7 after loading EBuddy on ITouch

I have a Toshiba laptop that came with Messenger installed. All worked fine until I loaded the EBuddy application onto my ITouch, allowing me to be logged on in two places. Messenger then logged itself out on my laptop and now will not work at all. When I try to sign in on the LT I get this message - Windows Live Messenger has stopped working. A problem caused the program to stop working correctly. Windows will close the program and notify you if a solution is available.
I've tried uninstalling all of Windows Live from the LT and EBuddy from the ITouch, then reinstalled Windows Live on the LT but I still get the same error message........anyone?

Make sure your Anitivirus program is not blocking Windows Live messenger. Which Antivirus program are you using ? If it is ok there than try to remove Windows Live Messenger from your system completely and reinstall again. For uninstalling WIndows live completely from your system,you can try MSN removal tool.

Thanks for responding.
I'm using Avast anti-virus software and haven't changed anything on that since it was installed on the PC. I've removed Messenger using the link you gave me then reinstalled it again from the msn site but to no avail. same error message coming up. any other ideas?

Simply go in C: \ Program Files \ Windows Live \ Messenger and then click on msnmsgr.exe. Then right click on the mouse and choose Properties. After that go to Compatibility and then click on run this program in compatibility mode. Check the box Open or Run as administrator and at last restart the computer. If still does not work then the messenger has some corrupt files in the registry or in the system folder. If can run system restore then that can help you.