I installed the 737NGX and it worked and the livery manager opened.When I went to download liveries it said there was a new version of livery manager so I downloaded it and extracted it into the Livery Manager folder under PMDG in FSX . Then the livery manager would not work even if I run it as administrator. If I choose compatibility mode it is greyed out so I can not select the run as administrator tick box.When I run the livery manager it freezes my computer but if I run task manager it says the livery manager application is waiting for a response from me but I cannot see a box to respond to.I guess this is something to do with the windows vista security settings.Has anyone any idea how to get the livery manager to work.Thank-you

Have you checked the extensive pinned post dedicated to liver manger problems?

I have resolved the problem by an unconventional route.i downloaded the latest version of Livery manager from PMDG site to my apple laptop. Then I sent it to myself as an email attachement. Then I downloaded the file to the desktop of my windows Vista computer and ran the file which was an exe file and it worked.All i can think of is that I had a corrupt download.Now I have managed to install a few liveries.

I have resolved the problem by an unconventional route.i downloaded the latest version of Livery manager from PMDG site to my apple laptop. Then I sent it to myself as an email attachement. Then I downloaded the file to the desktop of my windows Vista computer and ran the file which was an exe file and it worked.All i can think of is that I had a corrupt download.Now I have managed to install a few liveries.

It's because you used an apple in the process. Steve's residual karma fixed it.