Modifying the messenger .exe, a .dll or any other files that belong to Messenger will be "
You may not modify .. any ... software, ... products that are part of the Service except as expressly provided in these Terms of Use.So that will be illegal.
As far as bots:
You may not authorize any third party to access and/or use the Service on your behalf using any automated process such as a BOTI think this is more aimed at using a bot to allow MSN to interact with other networks (third party) like trillian/IRC and things. You bot won't be accesing the MSN service itself when you use the API to communicate. Your bot will use MSN Messenger and Messenger will communicate to the service then. That is as long as you don't communicate to the MSN protocol/servers directly but only through API.
In short, as long as you don't modify any of MSN's files and don't communicate to the MSN protocol/servers directly you should be fine. You can still communicate directly to your own server(s) or peer2peer between the users when you do that outside of the MSN protocol (MSN isn't peer2peer anyway). Using Messenger API is a good thing, hooking into MSN is a common thing too (just like Plus! does) but nut sure if it would be 100% legal. However, don't worry to much about these rules. As long as you clearly show you don't have bad intentions and keep away from modifying files/hacking into the protocol you should be fine. Patchou hooks into Plus! and made an option to hide the banner, which seems very bad for Microsoft. Yet Microsoft contacted him and even offered Patchou a job. Patchou didn't take the job because af some other reason, but from what i've heard the Messenger team still emails Patchou sometimes when they need his help
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Just to show how wierd an EULA can be sometimes: "
You may not ... transfer ... any information ... that are part of the Service except as expressly provided in these Terms of Use."
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