I just spoke with Angel @ PTC tech support(1-781-370-5204). To paraphrase her statement: "As we no longer support Mathcad 13, we can not verify whether or not Mathcad 13 is compatible or can be made compatible with Vista 64 bit. In some cases, the 'Run as Admin' setting may work, but we cannot...
I agree with brmech, I cannot get Mathcad 13 to run with Vista x64. Compatibility mode does not work, nor does "run as admin".
I am following a thread on this issue on the Mathcad forums:
http://collab.mathsoft.com/ type in "vista" in search query.
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