There is no one-fits-for-all installation order for FSX; especially when you have a number of addons to follow. Here is the order I took. Note that my FSX system and addons are stored on separate SSDs. Moreover, I used Acronis Home Image to backup each stage of my installation, just in case I need to go back to any point for any reason.
FSX-01-FSX Deluxe
FSX-02-FSX Acceleration
FSX-03-Scenery Tech Landclass
FSX-04-UTX USA, Canada, Europe and Alaska
FSX-05-GEX USA/Canada and Europe
FSX-06-Real Environment & Active Sky Evolution
FSX-07-Orbx Australia SP3 with mesh and updates
FSX-08-Orbx North West America with updates
FSX-09-Orbx Australia airports with updates
FSX-10-Orbx NA airports with updates
FSX-11-OZx and Ants airports
FSX-12-Must-use Scenery Addons
FSX-13-Current — updating with adding and removing addons
I store all these backups on a networked HDD. Total space consumed so far is about 300GB.
FS Times 
wow, it’s been a long time this article was written and still remains incredibly useful.
I just installed my Fsx copy, with acceleration expansion.
Then I’m about to buy and install: REX, UTX Eu/US, GEX Eu/US, ACCU-feel.
Are they fully compatible? Will the installation may actually affects they’re functionality?
In the end I would like to ask you if there is something that can improve entirely the cabin view mode, making it more customizable with better texture quality for the existing planes and that makes the navigation in the cabin through mouse possible (i.e. looking through the side glass, move the point of view between the two pilots, dezoom and extend the view to all the commands and intruments, etc.)
I’m playing at 1920×1080 and have no performance issues. Thank you very much in advance!
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Hi Dream Runner, REX, etc are all compatible with FSX.
For UTX and GEX, they are good and a must for FSX. They affect FSX performance a little, however.
Regarding your question about cabin view mode, you’d better look for the answer over the Internet and developers’ websites, because you are the only one knowing what you don’t like and what you want to improve.
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Thanks for your fast and reliable reply Tom!
I’m a bit sad because I still got problems with camera. It is so unfluent, and still works only with numpad or keeping mouse wheel pressed (only if EzCamera is active). It is so frustrating.
That said, I already installed EzDock Camera, and with it all the UTX and TEX addons. In the end I added REX, but it seems to be totally ineffective!
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Hi, FSX needs to be tuned for optimum performance. You can find some Posts about it in my blog or on the Internet. I guess it the cause of your problem.
For REX, you have to install it to FSX. Have you done so from the program’s menu?
Tom
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Thank you Tom
I had the concern and installed only REX 2.
Thank you for your help
Merry Xmass
Marc
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You are welcome, Marc.
Tom
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Hello Tom
I have just discovered your blog and it is fantastic. Thank you so much for the help you bring to flight simmer like me. I have installed and reinstalled FSX so many time, trying to improve my FPS.
When you install both REX and Active Sky, do they work properly together ? I mean ,is there any risk of conflict between them ? Or anything special in their respective setup to do ?
(Sorry for my English, I am french)
All my best and Merry Christmas to you.
Marc
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Hello Marc,
I don’t see any conflict between REX and Active Sky.
I installed all the textures and effects from REX to FSX directly. Then I use Active Sky to load the realtime weather. They work pretty well together in this way.
For the new Active Sky 2012, I haven’t tried it yet because the new version comes with effects and textures just like REX. I don’t know if there will be conflict.
Merry Christmas to you.
Tom
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