I recently started having problems with Mathcad embedded Excel. I kept getting the error "failed to launch server application". After trying to fix the Office install and trying to re-install Mathcad, I found the problem was an OLE error in Windows.
Start-> Run -> CMD -> and typing this statement fixed the problem:
regsvr32 c:\windows\system32\ole32.dll
Solution found at:
http://cissiecarrie.spaces.live.com/blog/cns!311F1F966CC26D61!901.entry?wa=wsignin1.0&sa=457888119
