I run IguanaTex 32-bit in Office 2010 32-bit / Windows 7 SP1 64x with MikTeX 2.9 32-bit. When I try to compile some TeX things with IguanaTeX to PPT, I get the error "Could not start process 'latex -interaction=batchmode "addin_tmp.tex"' GetLastError returned 0".
The prompt latex -interaction=batchmode "addin_tmp.tex" runs properly on PowerShell 32-bit and 64-bit and on cmd.exe (both in C:\Temp).
I already tried to repair and reinstall IguanaTeX and to run PPT with admin rights.
latex, maybe some security setting/virus scanner forbids the execution of the CreateProcess function. Other than that maybe try using TeXPoint. It's not free but has a 30 day trial and has the same requirements for the underlying LaTeX installation. – Alexander Jul 31 '12 at 16:52