TYPO3 Core

Yes i did, and this solved my problem :)
The difference is that the Install-Tool -> "try to fix" thing adds the web.config file automatically - which is not the case for apache (htaccess) or nginx.

All I would find nice would be if there was a little sentence added to it.
Something like: "hey for the IIS web.config to work you need the redirect plugin XYZ".
Cause it isn't mentioned here too: https://docs.typo3.org/m/typo3/guide-installation/master/en-us/In-depth/SystemRequirements/Index.html

Thank you :)

The documentation page where this information should belong is in my opinion this one: https://docs.typo3.org/m/typo3/guide-installation/master/en-us/In-depth/SystemRequirements/Index.html#microsoft-internet-information-services-iis

I have created a small pull request: https://github.com/TYPO3-Documentation/TYPO3CMS-Guide-Installation/pull/160 Please review if I have written everything correctly.

Are there other plugins needed?

Documentation has been updated; is there something that can still be done?

I don't know, it's okay for me.
I just don't know how you see it or want it, because TYPO3 reports the missing web.config file as "missing" in the install tool "try to fix" thing in contrast to apache, which doesn't report that the htaccess is missing...
It is not treated the same way. :)

But as I said for me personally ok, you can always improve something... ;)

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Other than that, I can't think of anything else at the moment - I'm just starting to get more involved with the IIS... :)

Thank you.