I have some URLs in an Excel file which I have saved as a .htm (webpage) file. I then view these in a browser via our wiki (MediaWiki). This is done using an iFrame embedded in the wiki page.

So, just for clarity, the link is in a htm file viewed via an iFrame in a wiki page.

When I click on that link, it opens inside the iFrame. What I want is for it to open in a new browser window. (This should be the user's default browser since some use Internet Explorer and some Firefox.)

The final twist is that some users have Windows XP and some Solaris.

Following the first answer I should clarify: I use Insert -> Hyperlink to add the URL to text in a cell (in Excel).

Help greatly appreciated.