Here I'll go into more specifics of what I have tried. So I've tried the newist generic synaptic driver. Ive tried many different versions of lenovo's drivers. Like a lot and multiple times for each.. Anyways the best current guess for what the problem might be I think is that the driver software might for some reason check to see if the machine I have is supposed to have the touchpad I have. From device manager I found that the hardware id of the tochpad is *LEN0034 which after a google search I found that this device is assosiated with the T540p. And I have a W540. Although it fits in fine and plugs in fine and should work fully fine and I see no reason why it shouldnt. Anyways I downloaded the newest touchpad drivers for the T540p, but as I suspected they are the exact same drivers offered for the W540 and W541.
One thing I tried doing was changing the hardware id of my W540 to match the id of a W541, but that resulted in 0 change.
Every once in a while when i try to open mouse settings it will pop up with an error message saying the synaptics driver is not installed or that a synaptics device is not detected. In device manager the device is listed as Synaptics Pointing Device though, as it should be. The only thing that doesnt work with my touchpad is opening the advanced settings. Also Ive tried just navigating to and running the executable that in the Synaptics Program Files folder. But it just does nothing.
I was thinking maybe if there was some way to change the hardware id of the new touchpad to match that of one for the W541. But it seems dumb that those need to match so I'm not too optimistic about it.
