You can login with multiple id's on the sameYahoo messenger without anydownload or softwares .
Follow these steps :
1. Go to Start ----> Run . Type regedit, then enter .
2.Navigate to HKEY_CURRENT_USER ----> Software --->Yahoo --->pager--->Test
3.On the right page , right-click and choose new Dword value .
4.Rename it as ---> Plural
5.Double click and assign a decimal value of 1
Its done!!Now close registry and restart Yahoo messenger and try Multiple Login Just click your yahoo icon.When you log into one account successfully then click the icon again from the start menu/desktop and login to another account(s)
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