Problem with Yahoo Messenger !!!

Hi guys !!!
Not sure if i used the right section .... but seems to be having some probs with yahoo messenger !!
I sign in , then logg off to sign back in with my other id......the messenger closes .......and sometimes a pop-up appears saying that yahoo messenger has faced a problem and needs to close, stuff like that
Is anyone else facing this problem , or am i the only one ??.
Is the problem from yahoo server or is it just me ??
Kindly help guys !!!

 

And yeah, forgot about this , when i sign in yahoo mail , a pop up appears , its about some security warning. It asks me if i wanna proceed or not.
When i click on "yes" , i go to my mailbox, and when i click on "no" nothign happens .
Is this some new security thing that yahoo came up with or what ??
Pls let me guys !!!