I have an Acer Aspire 5335 my battery died on me suddely. And the next time i turned my Laptop back on my Keyboard would not work at all. I 1st though i had accidently put sticky keys on, Toggle Keys or Filter Keys. However this was not the case as i checked and neither of them where turned on. I then though that my BIOS or Hard Drive had been corrupted. (I have to plug a USB Keyboard into 1 of my Laptop Ports to be able to use the Keyboard) I have all ready tried all the different types of key combinations. Such as Fn+NumLock,Fn+Shirt,Fn+Tab,Fn+F11, Both Left and Right Shirt together (for 10 seconds & 20 minutes Nothing),Tried pressing them alternatively Nothing, Alt+Tab,Alt+F4, Tried the whole lot on all the websites (Tomshardware.com,ccm.net,tomsguide.com, ECT) TRIED All the Suggestions that People suggested Still do not fix my keyboard buttons. I would press a letter and it would type Numbers Plus Letters at the same time. For Example A1 3wo9, w?.
I tried taking my battery out and running my Laptop on just the Power Supply Only (Taking the Acer Battery out and only having the Black Power Cord Charger in only). It did not work. I used my brother's Laptop to Buy a NEW Acer Aspire 5335 Battery when it arrived i inserted the battery and left my Laptop to fully charge once fully charged. I turned the Laptop on once Logged-Into my Account i then opened up a Note Pad & typed in a Letter or 2 as usual it would not work & type other Letters and Numbers & even weird symbols. But no my keyboard was finally back to normal again. All the letters and numbers worked as normal AGAIN. To fix the Random letters and numbers all you have to do is Buy a New Battery (Making sure the NEW battery is the Correct Make & Model for your Laptop) wait for it to fully charge then try it and your keyboard should be back to normal again.