Win 8.1 Pro with mediacenter does not upgrade to RTM

I was able to upgrade a Win 8.1 Pro to 10240 Pro RTM without any problems.

However I have a Win 8.1 Pro with mediacenter and when I try to do the upgrade (run setup within the OS) I only have the option to do a clean install and not an upgrade and keep settings.

Is this normal behaviour with this build or am I doing something wrong..

MS have withdrawn WMC. So you need to find a replacement. A good alternative is SichboPVR.

MS have withdrawn WMC. So you need to find a replacement. A good alternative is SichboPVR.

I don't care about the mediacenter, I just want to be able to upgrade (and keep files and setttings) to the RTM, but it just wont do that.

You could try this, but it may be too much time and effort, and it may not affect your problem:
Media Center - Remove and Go Back to Windows 8 Pro

Can't see it being anything to do with media centre as there would be many thousands of affected updaters coming up soon with wiped drives! And mine was no problem way back in Oct.

Sorry, but can't help with what the problem may be.

Are you using the correct setup.exe - the one in /sources - and not the setup in the root of the iso as in step 5 here: Windows 10 - Dual Boot with Windows 7 or Windows 8 - Windows 10 blog

It's also discussed here where someone has the same problem as you in a Win10 TP install, apparently:

[Fix] This Upgrade Path is not Supported. Close Setup and Re-Launch from Root of Media or Pick Different Installation Choice - AskVG

Why use the one in sources and not the one in the root? What is the difference in what they do?

I was able to upgrade a Win 8.1 Pro to 10240 Pro RTM without any problems.

However I have a Win 8.1 Pro with mediacenter and when I try to do the upgrade (run setup within the OS) I only have the option to do a clean install and not an upgrade and keep settings.

Is this normal behaviour with this build or am I doing something wrong..

I did it twice with 1 computer and 1 vm that had media center. I am not sure whats going on with it for you. I know I had to confirm that media center was going away but after that it upgraded just fine.

Why use the one in sources and not the one in the root? What is the difference in what they do?

Setup in the root folder is the program that opens when the (DVD, or bootable ISO on a memory stick USB) disk is used as the boot-up medium. Specifically it opens in the WinPE on a ramdisk - the preinstallation environment in memory only - and has some slight differences from the setup in the sources folder, with slightly fewer options. WinPE is found in Boot.wim, in the sources folder.

Root Setup is used for clean installations so none of the previous OS files are in use.

Sources Setup is used for upgrades, and runs in the host windows environment when you open it from within Windows, when you either wish to upgrade or install to a different partition, or unallocated space on the disk.

It becomes more complicated because there are two more executables, Install.exe and Installprep.exe which are in Sources too which do similar tasks to setup.exe.

Being Microsoft Windows, much of the process is not documented, so curious folk find out by experimentation or trial and error, what is possible or not. This leads to some successes and some failures.

I'm sure that there are more experienced folk here who could give more complete answers.

I was able to upgrade a Win 8.1 Pro to 10240 Pro RTM without any problems.

However I have a Win 8.1 Pro with mediacenter and when I try to do the upgrade (run setup within the OS) I only have the option to do a clean install and not an upgrade and keep settings.

Is this normal behaviour with this build or am I doing something wrong..

Maybe that's a preview build problem. "Get Windows 10" says that WMC will be uninstalled during the upgrade meaning that other programs will be maintained.