A contact added, but unable to find it in the online messenger and in windows phone as well.

To start with, I bought a Windows phone recently and found out that MSN messenger and Facebook chat are integrated in the message hub of the phone. I used to chat with a friend through my old phone using Google client. Since I switched to a Windows phone, I thought it'd be better to use MSN messenger now, instead of a third party Google app. So I told her to make an MSN account, and added her in my contacts successfully.

Now coming to the actual problem. After adding her in my contacts, I couldn't see her online in my phone. So I tried using the online messenger on oulook.com, and I still couldn't see her online. She was there in the People hub of outlook.com, but not online. While trying to search her in the messenger pane, I couldn't even find her as an offline contact.

Since then, I've tried all sorts of solutions I could find: deleted her contact and added back, sent invitation to join my messenger (and she didn't get it), checked the privacy settings in her account and changed the permissions to 'public' most, even made a new account but still facing the same problem.

Additional info:

She added me in her contacts, and was able to see me online.

She could send me messages, which I didn't get in the online messenger, but could receive them in my phone with her email ID showing up (although i had saved her contact details under her name)

I could reply to her message, and it worked fine that way. But that doesn't solve our problem, because she'd be using the MSN client in her phone, where she cannot see me online.

Hope I've been clear enough explaining the issue, and it'd be solved at the earliest. I shall provide more information if needed..