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I find it's best to open a new browser window [CTRL-N] and navigate your way to the site you want to link to. Highlight and copy [CTRL-C] the URL (address) of the site, and then go back to your Mudcat message and paste [CTRL-V] the URL into your link. Be sure to include the http:// in that URL. The quotation marks are standard procedure, but most links and HTML tags work just fine without quotation marks.