Failed To Play Test Tone Windows 7

Suddenly my ACER 4745G can't play music.
I checked in control panel > hardware & sound > sound >  speaker > test, error "Failed To Play Test Tone".
I reinstalled sound driver but it's not working.

After a few reading finally i saved (again) with windows 7 special command:
SFC /SCANNOW
Run "cmd" as administrator > type sfc /scannow > wait process to finish > done.
My laptop sound back to normal.

Thx Windows 7, you are so cool!

Ubuntu 9.10 black screen problem after loading (solved)

Today problem: my customer computer (ubuntu 9.10) stuck with black screen after loading.

To see the problem details:

• Enter the grub menu (press F2)
• Press "E" to edit boot command
• Delete text "quite splash" to see booting details
• Press control+X to boot

If you see like this:
"Gave up wiating for root device. Common problems:
  - Boot args
    - check rootdelay= ...
    - check root= ...
 - missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/disk/by-uuid/15448888-84a0-4ccf-a02a-0feb3f150a84 does not exist. Dropping to a shell!
BusyBox Built In Shell ...
(initramfs)

You have same problem with me, so this is the solutions:

• Find your root drive partition, example "/dev/sda1"
• Enter grub menu (press F2)
• Press "E" to edit grub command
• Change text "linux /boot/vmlinuz-2.6.31-16-generic root=UUID=xxxxxxxxxxxxxxxx ro quiet splash" with "linux /boot/vmlinuz-2.6.31-16-generic root=/dev/sdaXX ro quiet splash".
• Press ctrl+E to boot
• Finish, you can access your ubuntu again ;)

Source:
http://computergyan.wordpress.com/2009/12/31/solving-the-busybox-black-screen-problem-in-grub2ubuntu9-10/
Thx to this blog.

Can't turn on file and printer sharing (save didn't work) windows 7

Today i've got a problem, i can't change my file and printer settings (i saved the setting and after i view back it doesn't change old settings):

• i can't share folder and printer settings (Control Panel\Network and Internet\Network and Sharing Center\Advanced sharing settings)
• i can't view devices and printers (Control Panel\Hardware and Sound\Devices and Printers)

My OS is Windows 7 Ultimate, i remember that in the morning my laptop was crash and reboot automatically.

After searching in some forums and google, i found this command:
SFC /SCANNOW
Run as administartor > wait the process to finish > restart your computer > done.
I can share my folder and printer again, and i can access view devices and printers again.
Thx to google and people in that forum.


The description of "sfc" command:
Scans the integrity of all protected system files and replaces incorrect versions with correct Microsoft versions. <-- COOL!!!

/SCANNOW:       
Scans integrity of all protected system files and repairs files with problems when possible.

Some links:
http://www.sevenforums.com/tutorials/1538-sfc-scannow-command-system-file-checker.html