I have a acer aspire 5736z , suddenly my fn key all others that work in conjunction stopped functioning all over sudden, the Esc key too,please help

SOURCE: Pioneer DVR-K17RS ATA ACER CODE=39

it's windows issue, you just need to edit windows registry.
Follow this step from microsoft:
http://support.microsoft.com/kb/314060

SOURCE: Pioneer DVR-K17RS ATA ACER CODE=39

Hi, the error code that you have is a known issue from Microsoft that needs a registry tweaks. Error code means "Windows cannot load the device driver for this hardware. The driver may be corrupted or missing. (code 39)". You can click on this link for your reference http://support.microsoft.com/kb/929461/en-us

To resolve this problem, remove the affected filter drivers. To do this, follow these steps:1. Click Start, type regedit in the Start Search box, and then click regedit in the Programs list.
If you are prompted for an administrator password or confirmation, type your password, or click Continue.
2. Locate, and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318}
Caution There can be many instances of the registry subkey that is mentioned in step 2. You must make sure that you are in the appropriate registry subkey before modifying the UpperFilters and the LowerFilters values. To verify that you are in the appropriate registry subkey, make sure that the Default data value is DVD/CD-ROM and the Class data value is CDROM.
3. In the right pane, right-click UpperFilters, and then click Delete.
4. Click Yes to confirm the removal of the UpperFilters registry entry.
5. In the right pane, right-click LowerFilters, and then click Delete.
6. Click Yes to confirm the removal of the LowerFilters registry entry.
7. Exit Registry Editor, and then restart the computer.

This will surely help you resolve your issue. Good Luck!!!

Thanks

SOURCE: Function Buttons are not working in conjunction with (FN) Key for Screen light adjustment and other features.

As far I know FN keys are related with specific motherboard drivers.
Thoshiba recovery cd/dvd during restore/re-install, loads all toshiba drivers and utilities for operating fn keys.
If the operative system loaded in the laptop is no OEM then you will have this problem, and in order to fix it you must:
First install the operative system (clean install)
Second install: chipset drivers. This drivers instructs the operative system how to detect specific hardware. Must be installed in first order.
Third: install drivers (ethernet card, audio, video controller, toshiba utilities, etc). At this point verify all FN keys ( check display settings, stand by/ hybernation, etc).
four: Load all software needed (microsoft office, etc).

I hope this help to solve your problem

Posted by MCampos

SOURCE: I have an Acer Aspire

Hi malaynagl, try "restarting the computer."
"Sometimes all the troubleshooting will not fix the 'problem',
if the solutions aren't worked-out from "scratch!"
Restarting the computer can "help the computer reconfigure
"OS, Applications, and Services" back to the "Default State."
Once you 'press the FN / F2 combination; give the "connection time to receive a signal.
Go to the "Start Search Window," type in: window mobility center.
If you have this program?
Check the: "Wireless {Off / On} Switch?
"Use either the "Battery or Power Adapter" separately!.
Make sure the battery has a 100% charge before using.
Remove the battery when fully charged.
Let the battery drain to the point of an "Alert!"
About 10%
"Low Battery" icons' displayed!
Then; "rechared the battery
!Important: "Take a 'moment to rate the help', so I can get 'credit' for the work.

Thank you!" - paul7of9

SOURCE: I have an asus k40ij

reinstaling you operating system is one way of recovering these functions ,,make sure you are using a compatable os version and be wary to choose the correct options when installing at start-up point.