Re: i try to install lightroom 5.6 and receive Exit Code: 7 ERROR: Third party payload installer Adobe_Lightroom_x64.msi failed with exit code: 1603

Thanks for the update Sallwitz.  That makes sense as the Exit Code 7 is due to a file permission failure.  If you continue to experience any other difficulties you may want to look at migrating your documents and settings to a new User account.