TrackPoint Drivers for ThinkPad 25

Synaptics has updated the driver of the touchpad of the ThinkPad 25. A bug in the driver causes the user's setting for TrackPoint speed to be ignred. These buggy drivers are published to Windows Update and are thus forcibly installed. In order to restore the old drivers, the following steps must be performed. Credit to DaddyLongLegs on ThinkPad Forums

1. You need to download Synaptics Pointing Device Driver 19.5.19.28 for Windows 10 v1803 64-bit. This exact version must be downloaded.
2. Once downloaded, it will be a .cab file. Extract the cab file using 7zip, WinRar or similar.
3. Install the driver as your Synaptics Pointing Device by doing this: Right click each individual .INF file in the extracted .cab folder (the folder should be named ea10cb2d-3433-48cb-ba3a-b487acb7c014_ea74f9717ecb9763af8dd7eb8bf3dacd64c8ac6a) and click "install" for each INF file.
4. Go to Device Manager and right click on "Synaptics Pointing Device" under "Mice and other pointing devices". Choose "Update drivers" and then "browse my computer for drivers".
5. Choose "Let me pick from a list of available drivers on my computer" and then "have disk". Then point the file browser to your extracted .cab folder and select your INFs from there. Windows will complain about you having a newer driver but ignore that and force install 19.5.19.28.
6. Once the driver is installed (you may have to reboot before doing the following), here is where we finally unlock our TrackPoint sensitivity options for the T25: open the extracted cab folder again. The certificate used to sign the Synaptics app installer is expired as of August 4, 2018. It can still be installed by performing the following steps. There are two files with the .appx extensions (SynUWPCPL_19005.19028.0.0_x64.appx and SynUWPStickCPL_19005.19028.0.0_x64.appx). Do the following to each .appx file, individually:
   1. Right click the *.appx installer file and select Properties.
   2. Go to Digital Signatures tab.
   3. Select the certificate in the list and click Details.
   4. Click the View Certificate button.
   5. Click Install Certificate button near the bottom.
   6. Select Local Machine in the Certificate Import Wizard and click next.
   7. Select Place all Certificates in the Following Store and click Browse.
   8. Select Trusted Root Certification Authorities and press OK.
   9. Click next, then Finish.
   10. OK out of all the dialog boxes and try to install again.
7. Reboot. Now you will have a TrackPoint option in the Windows 10 "metro" style settings menu where you can finally adjust the sensitivity of the TrackPoint again! (see image below)

After you do this, you might want to enable a group policy to dis-allow Windows 10 from updating your mouse drivers, ever. Because it will "overwrite" these. There's a lot of guides on how to do it; there's also a registry trick to block automatic updates for specific devices too.