Solved
Prime 9.0 XMCD,MCD Converter tab is greyed out
XMCD,MCD Converter tab is greyed out. i need to open a .XMCD file created in Mathcad 15

When you installed Mathcad Prime, did you check the box to install the XMCD, MCD Converter as well?
If not, you should reinstall it and check that box.
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