Most of the Users complain stating Outlook Failed to Start, receiving startup errors. Few users tend to restart the Computer or end the program using Task Manager.

The cause might be various to isolate, make sure that we are checking step by step:

1. Profile corruption
2. Anti-Spam
3. Virus attack
4. Add-ins

Safe Mode

If Outlook worked or opened in right way before shutting down your computer, and error while startup.

Try to start the Outlook in Safe mode

To start Outlook in Safe Mode you’ll need to start Outlook with the “safe” switch;

• Windows 7
  Start-> type; outlook.exe /safe
• Windows 8
  Start Screen-> type; outlook.exe /safe
  (just start typing, a search box will automatically become visible)

When typing, please note the space between outlook.exe and /safe.

For alternative methods of starting Outlook in Safe Mode

Solution:

If it works in Outlook Safe Mode, the issue is most likely caused by an add-in, a corrupted settings file or the first message that is being displayed when Outlook is started. See the next 3 troubleshooting steps below for further analysis of the issue. If it doesn’t work in Safe Mode either, the next 3 steps will probably not help you either to solve it and you can continue with Scanning your pst-file for errors.

Use scanpst.exe to fix Outlook Data File errors

When you use a pst-file, it could be that an issue with that pst-file is preventing Outlook from starting correctly. Often this issue is accompanied by the message;

“Errors have been detected in the file <path to pst-file>. Quit all mail-enabled applications, and then use the Inbox Repair Tool.“

Solution:

Use scanpst.exe to scan the mentioned pst-file for errors. The location of scanpst.exe depends on your version and language of Outlook.

• Outlook 2013
  32-bit Windows: C:\Program Files\Microsoft Office\Office15
  64-bit Windows: C:\Program Files (x86)\Microsoft Office\Office15
  64-bit Outlook: C:\Program Files\Microsoft Office\Office15
  Office 365: C:\Program Files\Microsoft Office 15\root\office15
• Outlook 2010
  32-bit Windows: C:\Program Files\Microsoft Office\Office14
  64-bit Windows: C:\Program Files (x86)\Microsoft Office\Office14
  64-bit Outlook: C:\Program Files\Microsoft Office\Office14

Prevent pst-file corruptions

Preventing is better than repairing of course. While there have been a lot of precautions built into Outlook to prevent pst-file corruptions, there are a couple of common causes which may result in corruptions in the pst-file;

• Computer/Outlook crashes
  If your computer crashes while Outlook was running or even worse, writing data to your pst-file, running scanpst.exe afterwards is highly recommended. Always try to find the root cause of your computer crashes and make frequent backups of your pst-file when you cannot directly find the cause (actually, making backups frequently is always recommended).
• Outlook not closing properly
  If Outlook doesn’t close properly (the outlook.exe process continues to run after you close Outlook), then Outlook will be closed forcefully when shutting down your PC which is similar to Outlook crashing. To troubleshoot see; Outlook doesn’t close
• Faulty add-ins which write corrupted data
  While add-ins are great to extend the functionality of Outlook, they might not all work as expected. If corruptions continue to occur in your pst-file, it might be good to review your installed add-ins and see if you still need them or if an update is available. You might be even using some without knowing. Disable them all and see if the corruptions return. If not, test them one-by-one to find the culprit. For more info see; Enable/Disable add-ins
• Storing your pst-file on a network share
  Pst-files are designed to work from a local hard drive. Using pst-files from a network share is not supported by Microsoft and could lead to poor performance, data corruption or even data loss.
  If you are using Outlook 2010 and have your My Documents folder redirected to a network share, you might be using your pst-file from a network share without realizing it.

Praveen

MCTS | Exchange Server