I have installed two versions of FS on my PC and they do work independently, one on my C: drive (which was the original weighing in at around 25gb), which has the 733NG and 744 installedTo enable me to install another copy of FS I did the following:-I renamed the .cfg and .exe files to FSold.cfg and FSold.exe this then enabled me to install a second parallel version of FS on my new F: drive. I have now discovered that the new version does install a new .cfg in the C: drive (which is not a problem) so they are all working ok? The only trouble is that add-ons like the PMDG 737 series and 'the Queen 744' can only be installed on one version; when I try to install another copy, I receive a warning message saying that this product is already installed? - is there a way round this, so I can have both a/c on the two separate drives (C: and F:)? The same goes for Active Sky is this possible to have two independant versions? without this program FS is not worth flying (a little harsh I suppose)... :-)CheersPHIL

Anybody - assistance is much appreciatedThanksPHIL

Have you tried simply copying the entire aircraft folder, the gauges, etc. to the 2nd drive?With some projects relying on license check files, it is quite possible that you won't have complete success...