I can't open any tiles, like mail ,bing ,store aps. I can get to my desktop but can't open anything on it.

It seems that you are unable to open any Windows 8 Apps from the Start Screen of the computer. I can definitely help you with this issue.

1) What exactly happens when you try to access the Windows 8 Apps from the Start Screen?

2) Do you get any error message when you try to open the Apps?

3) Do you have any third party security program installed on the computer?

4) Have you made any recent changes on the computer prior to this issue?

5) Is this the first time you are trying to open the Apps after installing Windows 8 or were you able to access them before?

You need at least 1024 X 768 screen resolution for Metro apps to work. The Windows apps will not work in screen resolution less than 1024 X 768. To snap apps, you need a screen resolution of at least 1366 x 768. Make sure that the screen resolution meets these requirements. You can check this by:

a) Right-click the mouse from the desktop interface and select “Screen Resolution” from the menu.

b) Check the screen resolution shown there. It should be at least 1024 X 768.

Also, make sure the User Account Control (UAC) is enabled in the computer. To enable the User Account Control on the computer follow these steps:

a) Press “Windows Logo” + “W”, type “Account Control” in the search bar and press “Enter”.

b) In the “User Account Control Settings” window, move the slider to the default settings and click “OK”.

Let’s try out some basic troubleshooting steps and check the issue.

Method 1: Run the Apps Troubleshooter

Let’s first run the Apps Troubleshooter and check if that helps. The Apps Troubleshooter is an automated tool which we have developed to address a number of known issues that can prevent the Apps from running properly. This troubleshooter automatically fixes some issues, including suboptimal screen resolution, incorrect security or account settings etc. You can click on this link to download and run the Apps troubleshooter.

http://download.microsoft.com/download/F/2/4/F24D0C03-4181-4E5B-A23B-5C3A6B5974E3/apps.diagcab