Skins have never touched msncore.dll. MSN Messenger held its resources in the main executable (
msnmsgr.exe) and Windows Live Messenger keeps its resources in (
msgsres.dll). It would help a lot if you told us what version of MSN/ Windows Live Messenger you were using, and what skin you were trying to install.
Follow Sunshine's instructions, it will make sure all files Messenger needs are installed
.
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