Patching 11.0.2 AIP with 11.0.3 not working

I have an AIP with Reader 11.0.2 and distribute by GPO which is working fine.

I now tried to patch the AIP with 11.0.3 - as I did before for 11.0.2 - but I get an error. It tells something like program not there or wrong version.

msiexec /a AcroRead.msi /p AdbeRdrUpd11003.msp

What am I doing wrong?

Thanks

McL