***Attention! If you miss MSN/Windows Live Messenger, AIM, and/or ICQ, this is for you! If you use a screen reader and want a 100% accessible messenger client, this is also for you.*
This works with Windows XPthrough 11, and I'm logged into it as I write! It's called Escargot, and it revives Windows Live/MSN Messenger. This is the original software, but it has been patched so that it connects to the escargot.chat server and not the Microsoft one. It is 100% free and accessible with NVDA and I'm sure JAWS as well. They also have projects for AIM (AOL Instant Messenger) and ICQ, including for Android and IOS, and are working on a web client for MSN. (I don't know if AIM or ICQ are accessible with screen readers, as I have never tried them). Anyway, if you're over twenty-one (my personal request), have read my profile here, and wish to add me, I am dandylover1@escargot.chat. You can find everything here.
Note: If you already have Windows Live/MSN Messenger on your system, you will still need to download their version and create an account. Your Microsoft, MSN, or Hotmail one won't work for signing in. Also, remember to click on RUN_AFTER_INSTALL.exe, in order to patch the program to the Escargot server.