Method1:
Try to open Outlook in safe mode. Follow thses steps to do it.

1.Click on start button (for Vista it will be Windows button ) and click on Run.
2.Type outlook.exe /safe and press enter.
3.If outlook is not starting then we have to do a detect and repair. Follow these steps to do that.
Detect and repair.

1.Click on Start button (for Vista it will be Windows button ) and click on Run.
2.Type outlook.exe /safe and press enter.
3.Go to Help tab in Outlook and select office diagnostics, click on continue and click on Run Diagnostics.

Method2:

Try to open Outlook without addins.

1.Click on start button and click on Run.
2.Type outlook.exe /a and press enter.

If he can open Outlook in this way, then the third party addins are causing the issue. This can be resolved by
removing the third party addins. Follow these steps to remove third party addins.

1.Open Outlok and click On the Tools menu, click Trust Center, and then click Add-ins.(for Office 2007).
2.In the Add-ins box, identify the add-in that you want to disable and note the Add-in type located in the Type
column.
3.Select the Add-in type in the Manage box and then click Go.
4.clear the check box for the Add-in that you want to disable and then click OK.

Method3:

WE have to use Inbox repair tool for scanning the pst files. Follow the below steps.

For Windows Vista generally pst file wiil be located at this location: disk

disk drive(normally Cdrive):\users\username\AppData\Local\Microsoft\Outlook

Windows XP and Windows 2000: disk drive:\Documents and Settings\username\Local Settings\Application Data\Microsoft\Outlook

For runnung Inbox repair tools, follow these steps.

1.Exit Outlook.
2.Open My computer and click on Tools and select Folder options. Click on View and select "show Hidden files and folders."
3.Click Start, and then click Find or Search, depending on which version of Windows that you are running.
4.In the search box, type Scanpst.exe.
5.Double-click the Scanpst.exe file to open the program.
6.Click Browse to locate the .pst file. Normalyy it will be in this location.



*Windows 98 or Windows Me: disk drive\Windows\ Local Settings\Application Data
*Windows NT 4.0: disk drive\WINNT\Profiles\username\Local Settings\Application Data
*Windows XP or Windows Server 2003: disk drive:\Documents and Settings\username\Local Settings\Application *Data\Microsoft\Outlook
*Windows Vista: disk disk drive:\users\username\AppData\Local\Microsoft\Outlook



7.Click Start. The Inbox Repair Tool scans the file and reports whether it found any errors.
8.Click OK.

Method4:

Press Cntrl+Alt+Delete to open task manager and click on processes. click on outlook.exe and click on End process.
If there is multiple outlook.exe running end all of them. Try to open outlook after ending all outlook.exe processes.



Method5:

Outlook express wil not start if there is missing or corrupted information in the Outlook Express Identities registry key. WE have to
modify the registry. Before editing bthe registry we have to take the backup of registry file. Follow these steps to take a backup of registry.
This is somewhat long and complex process.

For Vista:

*Click Start, type systempropertiesprotection in the Start Search box, and then press ENTER.
*If you are prompted for an administrator password or for a confirmation, type the password, or click Allow.
*Wait for Windows to search for available disks and most recent restore points. In the System Properties dialog box,
on the System Protection tab, click Create.
*Type a name for the restore point and then click Create.
*After the restore point has been created successfully, click OK two times.

NOW WE HAVE TO Rename the "Main Identity" Subkey, fOLLOW THESE STEPS.



1.Click Start, and then click Run.
2.In the Open box, type regedit.
3.Locate the following registry subkey: HKEY_CURRENT_USER/Identities
4.To do so, in the left pane, click the plus sign (+) that is next to each registry key or subkey in the path to expand each branch until you
locate the subkey that you want to delete. For example, in the following registry subkey path, the subkey is Identities:
HKEY_CURRENT_USER\Identities
5.In the left pane, click the plus sign (+) that is nex__TEXT IS TOO BIG. IT WAS TRUNCATED TO 5000 SYMBOLS

Thank you. The issue has been resolved.