Alt+Ctrl+Del not working for logon .... IT experts please help

Hello IT gentlemen/ladies. This is a Win7 forum and I have XP, but still would post as help needed asap. I am a Mechanical Engineer working offsite, with minimal IT background. I work offsite and do not have proper access to IT department of my company(or, in this case, I dont want to bother IT department)

So, here is the issue: On the other day I spill glass of water on my work HP Elitebook. Keyboard was covered with water. Laptop was OFF at the time. So, I took out battery, left it to dry for 3 days with a fan and very low heat(far away - warm only) air under supervision. I also lifted the keypad to dry within, although I didnt notice much water. I also removed the hard disc to dry on the lower side......3 days to dry and today i put back the keyboard(was not disconnected, just lifted) and HD back in. I was extra careful in this disassembly/assembly process.

I booted the system. It started fine/normal but when it goes to Ctrl+Alt+Del, nothing happens, so cant put my login info to start. Basically computer acts as if I didnt press ctrl+alt+del at all. \
Main mouse of laptop work, as well as the little mouse in middle of keys on keypad.
I tried safe mode, same thing. I tried another keyboard as USB attachment, same thing.
Even the laptop keys seem fine as up-down keys work(went to safe mode with F8), etc

I am badly stuck. Cant call IT folks because I work remotely and also dont want to disclose the water story. PLEASE help ASAP if possible. Has this got anything to do with removing and putting back the Hard drive.

Might be a daft question, but when you lifted the keyboard to dry it underneath, you didn't accidentally disconnect or forget to reconnect the keyboard did you?

Really appreciate the reply. Keyboard is well connected. But in general, you are correct- I went to Staples and bought a Microsoft wired(so that I don't have to install drivers, as I can't login) USB keyboard. Plugged it in ad it's working!! Looks like keyboard had been sacrificed to prevent water damage to main laptop components. It is working expect keyboard which I will now use the uSB one. Glad i can do my job now with this laptop (except keyboard)

Thanks for the reply though!!!

How was the USB keyboard you tried in post #1 was different than the Microsoft one? Wireless?

Tried reseating the keyboard plug back in? (possibly just a ribbon?)