I am creating an addin for Outlook, and I would like to use some standard microsoft's icons in my addin's GUI - for example, outlook has 'reply to' icon that people already know well, and I would like to use the exact same icon for replying action in my addin.
Is it legal to do this? According to http://www.microsoft.com/about/legal/permissions/default.mspx#EDE Microsoft is very strict and does not allow reusing their icons in other software (except for icons delivered in their development tools).
However, this would be pretty unpractical, as I would have to design my own 'reply to' icon, which should be as similar as possible to the standard one (in order to not scare users), while being different enough to stand up in a court. I find this pretty crazy and indeed, there are icon vendors who sell icon sets 'almost' copied from Vista (example here) - how legal is this - I'm not sure their folder or printer icon could be defended in a legal case?
And besides, what if I use tree control in my app, which automatically contains microsoft's icons, or what if I display files that are associated to default windows programs and therefore have their icons?
Have you used MS icons in your app? Or do you know about some place where I could find out these questions? Thank you!
EDIT: the first link actually covers only product icons - for example icon of Word 2007; it says nothing about icons used in app.