Dell m4400 Touchpad dosen't work

[old pc gamer]

Hello guys . i have a problem . i found an old dell m4400 when i helped a friend to move out . he told me to keep the laptop soo i started to clean it . the laptop is working fine . i bought an replacement keyboard because the old one had missing buttons . So i swaped them but now the touchpad and the trackpad dosen't work . not anymore .
I tried to swap with the old one back but same results
The laptop specs:
Cpu- Core 2 duo p8700
Ram- 4 gb ddr 2
HDD- WD Black 320 gb ( not sure how many rpm )
The laptop is working fine with an mouse but i like to use it more with a touchpad
What would cause this ?
i was very carefull when i took the old keyboard back to don't bend or brake something under it
If someone know what should i do i would be really gratefull
Thank you for help !!!

 

[reedo_43]

I would open it up again and make sure the ribbon cable from the touch pad to the mb is secure. Worst case
https/www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR0.TRC0.H1.TRS3&_nkw=Dell+m4400+Touchpad&_sacat=0

 

[old pc gamer]

Ok i will try to open it again and check if everything is secure .