Messpatch doesn't boost your PSM to an unlimited length, so it will always be limited.
quote:
Messpatch Help site
Boost Personal Messages To 500 Characters
Increases the maximum allowed length for personal messages to 500 characters.
By default, personal messages have a maximum length of 128 characters. Selecting this option will increase that to 500 characters however, you will only be able to see whatever is beyond 128 characters in tooltips and conversations
If there are some plugins/addons/patches in the way, reinstall Windows Live Messenger and use messpatch before you reinstall the other plugins, patches and/or addons.
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