i have a problem with my messenger currently

i have downloaded msg plus from the site and installed it on my windows live messenger
but once the installation has finished, my messenge just shuts down completely.
i try load it again several times yet it still doesn't come out
i know its there though because its in the processes.
im sure its not locked or anything
this only occurs once messenger plus in installed, once i uninstall it, my messenger comes back normally.

could it be that my anti-virus or something has blocked it?

im currently using windows live messenger 8.5

if someone could help me it would so greatful !
thank you very much,

try uninstalling plus. Then making sure you have exited WLM. Then try reinstalling.

That's what happend to me, but the above of the post doesn't work on mine...