I have been playing around with XP SP3 / Windows Messenger 4.7.0105 and I have created an installer that works without users needing to import a registry file. So it works out of the box. I have tested this in a VM BOX fresh and the installer is 0.98MB.
Could someone else please test this for me in a VM. Basically it extracts the setup to %temp% and calls this batch file.
START Setup.exe /Q
REG IMPORT SETSER~1.REG
Windows Messenger 4.7 PATCHED.zip (972.4 KB)