Clean install while keeping existing partitions?

the tutorial here says to delete all partitions before clean installing windows 10. But I don't want to do that.

I just want to reinstall cleanly on the OS partition only.

In the past with win7, when I had an OS and Data partition, I would just reinstall the OS, and my data would be intact.

Can the same be done with Win10 ? keeping my Data partition untouched?

Can the same be done with Win10 ? keeping my Data partition untouched?

Yes. Just delete the Windows OS partitions. Leave your data partition intact.

I would delete all partitions but the data partition or you can end up with a real mish-mash of partitions.

the tutorial here says to delete all partitions before clean installing windows 10. But I don't want to do that.

I just want to reinstall cleanly on the OS partition only.

In the past with win7, when I had an OS and Data partition, I would just reinstall the OS, and my data would be intact.

Can the same be done with Win10 ? keeping my Data partition untouched?

To me doing a clean install means the drive is in the same condition as received from the factory, absolutely nothing on it. To that end I Copy/Move everything I want to keep, that exists nowhere else, to another drive and assure the discs or downloads of programs I want to install are at hand for installing. Then I use a bootable partitioning program such as GPARTED to wipe the drive clean. Windows, and particularly 10, seems to like it better that way and there's not much to be careful of, just accept the defaults and work with setting it up later as desired.

I would delete all partitions but the data partition or you can end up with a real mish-mash of partitions.

Agreed. Hopefully the data partition is at the end of the disc. If it isn't at the end of the disc, I would move it there. Then install Windows 10 to the unallocated space left in front of the data partition.

I am at the point where a windows 10 pro upgrade is totally stuck - after 3 weeks - and I have to bite the bullet and choose the win 10 reset. Now my PC has 2 drives with several partitions and a dual boot set up.
Win 10 offers to keep my files and setting but then says, that it will delete everything on the PC, i.e. the whole computer, that did not come with the PC. Does this mean windows 10 will WIPE everything on 2 drives including all data partitions and the other OS?

Does this mean windows 10 will WIPE everything on 2 drives including all data partitions and the other OS?

It's hard to say what will happen when you select Windows 10 reset. I would do this instead:
Repair Install Windows 10 with an In-place Upgrade - Windows 10 blog

I bit the bullet and chose "Reset" in the Win 10 options.
It leaves other partitions and OSs alone and only pastes a new install onto the existing Windows 10. It recoveres the windows activation key. You will be the disc jokey afterwards to install all your beloved old programms though.