since i bought the adobe suite in 2018, i now have photoshop version 2018, 2019, 2020 and 21.
What should i do with th older version. Why not clean the mup automaticly?
You can uninstall them, but you need to be a little careful and follow version order.
File associations - which application automatically opens a given file type - will always stick to the latest version you installed or uninstalled. If you install 2018 after 2020, then your image files will automatically open in 2018.
It also works the other way. When you uninstall, file associations are handed back to the OS. If you now uninstall 2018, it will often take the file associations with it, leaving 2020 orphaned. Sometimes this gets stuck and cannot easily be reassigned.
To avoid all this, always follow version sequence. To uninstall, start with the newest and work backwards. Then reinstall the one you want to keep:
This has been an issue forever, and every time a new version is released, the forum is full of people with messed up file associations. The CC installer should be set up to do it like above, but for some reason it isn't. If you set the option to remove old versions, it will do that after the new one is installed.
Keep ones that work well for you as backup for when Adobe brakes PS the next time. Just delete the ones you dom't want do not use Adobe uninstallers they may mess up the current version system configuration.
if "do not use Adobe uninstallers" what else should i use ?
You have to use Adobe uninstallers. Just do it in sequence as I described above, and you'll be fine.
There is a difference between an update and a full new version of Adobe apps. The smaller incremental updates build on the current version, but the new versions are completely new applications, and many people like to keep an older version or two based on their needs.
I haven't run into issues using the provided uninstallers to remove the old version, but if you do, you can always simply re-install the current version.
"you can always simply re-install the current version."
That's the point; that isn't always enough. Sometimes you need to run the full cleaner tool routine, or go in and edit the registry. This isn't me, this is what I see in the forums every time a new version comes out - all the way back as far as I can remember (at least CS2).
This is a side effect of having several independent applications that all claim the same file associations.
Usually it works out and the associations can be easily reset. But not always, and if you want to be sure to avoid problems, do it as I described above. Then you're safe.