After disassembling my Presario 2100 to resolder the DC jack, the computer no longer recognizes the touchpad, and the LEDs for 'on/standby' and 'battery charging' no longer work.
Strangely, the LED for hard-drive activity does work.
The touchpad ribbon cable is connected. I am 99.999% it is seated all the way because I triend re-inserting it many times.
External PS/2 mouse works just fine.
In the Control Panel > Mouse there is no choice for touchpad, only the PS/2 mouse (when it's attached).
*However* - in the Properties and other tabs, it says 'Synaptics TouchPad Properties Version 6.7.4' etc. and clicking on 'Settings' brings up the Synaptics window, which is what you would see when the touchpad was working. But instead of having all the advanced settings for touchpad features, it says 'Properties for Standard Mouse on PS/2 Port'.
There were never any problems or unusual behavior with the touchpad before.
I went into BIOS Setup and reset everything to the defaults.
What could be going on here? Could I have physically damaged anything? I have disassembled the laptop a couple times to clean out the fan and replace the keyboard, with no problems.
Compaq Presario 2100 AMD
40Gb, 756 Mb RAM
3 or 4 years old