MacOS High Sierra does not detect the trackpad, although it works

Same problem here, on same old Macbook Pro mid2010 that I use as secondary Mac (so I didn't check the first version of High Sierra with this issue). NVRAM and SMC reset didn't helped... I'll sand a Feedback to Apple about it.

Somebody else reported here the same issue: Cant change trackpad settings, please help!

and here: My in-built trackpad on my macbook pro is working fine but in settings it says "No trackpad found". Can't change or set up gestures for trackpad anymore. HELP!!!!

Ok, thanks for the feedback!
This seems to corroborate the info from the phone support and also the post you linked to earlier (My in-built trackpad on my macbook pro is working fine but in settings it says "No trackpad found". Can't change or set up gestures for trackpad anymore. HELP!!!!) stated that the battery had been taken out due to it being swollen.

If this really only applies to people who are running their (older) laptops without any internal batteries I'd sadly guess the chances of this bug ever getting fixed are pretty low.

The “fix” I found to make “tap to click” and other gestures work is installing El Capitan, enabling them, and updating to high sierra...

Won’t make trackpad settings show up, but at least we can use “tap to click” and mission control gestures...

I had the same issue on my mid 2011 MacBook Air 11".

This question might sound stupid, but do you have a battery installed?

Apple phone support just told me that it is a known but probably very low priority bug that High Sierra doesn't let you access the settings for the built-in trackpad if no battery is installed/recognised.

Background:

I did a clean install of High Sierra (10.13.3) and couldn't access the Trackpad settings as it would search for a Bluetooth trackpad similar to your description.

After consulting Apple's phone support I did SMC and PRAM resets and nothing worked.

A clean install of Sierra (10.12.6) on the same machine gave me access to the trackpad settings again.

I made the wished for adjustments in the trackpad settings and downloaded the High Sierra installer through the Mac App Store. After updating, I ended up with the same situation as before: No access to the trackpad settings.

I called Apple support again and a higher level support tech first walked me through resetting the Bluetooth module and then right away checked whether I have a battery installed and as a matter of fact I don't.
The battery expanded last year and I had it removed at an Apple Store, so I am only using the MacBook Air as a stationary device at home these days.

My only option at this point thus is to go back to Sierra and hope that a future update eventually addresses this bug, unless I want to invest in a battery replacement.

The question wasn't stupid! I had to remove the battery because it expanded. I might have to replace it, but as I said, that is a secondary Mac for me.

Good to know this is a known issue... I hope they solve it, High Sierra probably will be the last MacOS version for these old Macs...

And... What about changing trackpad settings directly from the .plist file in ~/Library/Preferences ?

I found com.apple.driver.AppleBluetoothMultitouch.trackpad.plist and it's easy to understand, but I haven't tried to change something yet

Did you solve it? I have a 2010 mba with the same issue on Sierra and High Sierra.