As we all know about Microsoft Outlook (especially professional people) which is an email client developed by Microsoft. In Microsoft Outlook premises error can be raised at any time. To fix such type of issues in MS Outlook, a user must have information regarding the causes of concerned error. Here, in this article, I am going to cover those common causes and their solutions that occurred mostly in MS Outlook.

1Cannot start MS Outlook :

If Microsoft Outlook displays an error: “Cannot start Microsoft Outlook. Cannot open the Outlook window” as shown in given screenshot, then there might be several cause behind appearing this error. Some of them are listed below:


  • According to the Microsoft, the main cause of this error is corrupted Navigation pane settings file i.e. profile name.xml. Basically, the profilename.xml is the name your Microsoft Outlook profile. When the size of file becomes 0 KB, it indicates that the file is corrupted.
  • When you are using Microsoft Outlook in compatibility mode, then this error may also come up.
  •  If Microsoft Outlook Data file have been deleted or damaged somehow, then this error might be extended.


  • Start MS Outlook in Safe Mode. To do so: Press “Start Key” + “R” >>Type “outlook.exe<space>/safe” in run dialog box.
  •  If Microsoft Outlook opens in safe mode, then remove add-ins by Clicking on the “File” tab >> “Options” >> “Add-Ins”>> Select “Com Add-ins” and click on “Go”  >> Clear all check boxes in the list & click “OK” button >> Restart “Microsoft Outlook” (normally, not in safe mode).
  • You can also create a new user profile in MS Outlook.
  • Even after creating a new user profile, if the problem remains same, then reset the navigation pane. To do so: Press “Window Key” + “R” >>Type “outlook.exe<space>/resetnavpane” in run dialog box.
  • Last but not the least, give a try to “SCANPST.EXE (Inbox Repair Tool”), which is a free (inbuilt) utility developed by Microsoft.
2. Microsoft Outlook takes too much time to load:

There might be many reasons that induce conflicts in Outlook and makes it slow. Here, in this section I am going to discuss some of those causes, which generally turn down the performance of Outlook.


  • Outlook users generally pick some add-ins to make outlook more feasible or can say speed up the various task, but unknowingly they called detrimental plug-ins, which does not prove much instrumental as in concerned manner they were added. As a result, such vile plug-ins increases the loading time of Outlook.
  • Supposedly, hefty Outlook Data file or when Outlook outruns by its default size, then Outlook starts mitigating the Outlook performance.


  • First of all, disable the Add-Ins. To do so, you can see the procedure above for disabling the Add-ins in MS Outlook.
  • Archive your over sized Outlook Data File. Remember, Archiving features in MS Outlook will take too much time, if the Outlook PST File is too large. As we all know that, nowadays most of the professional people have less time to spend on look over data. So, they can go with the any Split PST Tool to break their large Outlook Data File into smaller PST’s by Folder, Size, Date and Year.

3. Microsoft Outlook Unable to send Emails after upgrading from Window 8, 8.1 to Window 10:

To overcome this issue, you should run “SFC (System File Checker)”in command prompt:

To do so:

  • Type “Command Prompt” in search bar >> a command prompt icon will be shown to you, right click on it and select “Run as administrator” (look in screenshot).
  • Type “sfc<space>/scannow” in the command prompt. Wait until the process does not complete.
  •   Now, reboot your system.

Noteworthy thing:

4. Microsoft Outlook gets freeze or Hang/Outlook Not Responding:

Most of the time this error appears when you send any email or open a file in Microsoft Outlook 2010 or Microsoft Outlook 2013. The error appears like this:


  • Microsoft Outlook is in use by another process.
  •  Enabling of Add-Ins in access.
  • Corruption Outlook Profile.
  • Large Outlook Mailbox.
  • Corrupted or damaged Microsoft Outlook Data File.


  • The best solution which most of the time works is removing Outlook from Task Manager (In simple term, turning down Outlook using task manager). To do so: Press “Ctrl +Shift + Delete” (Combination) >> Go to “Task Manager” >> Select “Microsoft Outlook”>> click on “End Task”.
  • Try to open MS Outlook in safe mode.
  • Remove MS Outlook Add-ins.
  • Repair Outlook Data File.
  • Disable your antivirus Programs.
  • Reduce the size of Mailbox and Outlook PST File by using Compact Now Feature in MS Outlook.
  • Disable Hardware Graphics acceleration.
  • Use Microsoft Fix It Tool.
5. Microsoft Outlook error 0x800CCC0F:

Among all errors, MS Outlook error 0x800CCC0F is a staple problem and usually appears when you tried to send or receive emails in Microsoft Outlook. The Outlook shows the error message something like this: “Sending reported error (0X800CCC0F): "The connection to the server was interrupted" as shown in screenshot at the time of bug. Have a look at the main causes and solutions to fix the Outlook error 0x800CCC0F.



  •  MS Outlook error code 0x800CCC0F typically appears, when your antivirus program enabled in MS Outlook or its settings is relatively not analogous to Outlook.
  • Blocked advanced settings by ISP.
  • The Outlook error 0x800CCC0F may also appear when Microsoft Windows Firewall blocks MS Outlook.


  • Make sure that you are connected with Internet.To resolve this error, disable your antivirus program as well as Windows Firewall. Know how to disable Windows Firewall. Please follow the path: Press “Start” Key + “R” >> Type “Control Panel”& click on “OK” button >> click on “Network and sharing Center” >> Click on “Windows Firewall” (See bottom-left) >> Click on “Turn Windows Firewall on or off” >> a new window will open click on “Turn off Windows Firewall (not recommended)” for both Private and Public network settings.
Note:  These above steps that I defined are for MS Outlook 2010.

  • Make sure that Outgoing Server (SMTP) port is 25 and Incoming Server (POP3) port is 110 by default. To check it: Open "MS Outlook" >> Click on “File” Tab >> “Account Settings” >> “Account Settings” >> Click twice on your email account >> “More Settings” >> “Advanced” Tab.
  • If the above solutions unable to fix the issue, then it can be the issue of corrupted or damaged Outlook PST File. To repair minor level corruption in PST file, you should try to run SCANPST.EXE (Inbox Repair Tool) which is free tool developed by Microsoft. Sometimes, this tool fails to repair Outlook PST File just because it has has not developed to face highly corrupted PST File bugs. So, in such a scenario, you must need a commercial Outlook PST Repair Tool to repair highly corrupted Outlook Data.
6. Outlook PST File is not a personal Folder File.
There might be several reasons of appearing this error: “Outlook.pst is not a personal folders file”. Here, in this section, I am going to discuss some of the causes and their solutions to get over this error.



  • If your Outlook Data File is on CD/DVD or marked as “Read only” attribute, then in such a case this error will appear.
  • This message also appears when you import or restore corrupted Outlook PST File or split PST file into MS Outlook.
  • This error might be appearing if MS Outlook is running and randomly System shutdowns happen due to power failure. 


  • First, you have to copy Outlook PST File from the CD/DVD and paste on your local hard drive.I would like to suggest you to make a sub-folder named as “Outlook” of your Document Folder and put that PST file in Outlook Folder. After doing this, uncheck the attribute “Read Only” , if checked, To do so : Right Click on "PST" File >> Go to "Properties" >> Deselect the option: “Read Only”.

Note: Make sure that did not overwrite any existing Outlook Data File.

  • Do not import Outlook Data File, once you have restored the PST File by above method.
  • Proper way to open Outlook PST File: Click on "File" Tab >> "Open" >> "Open Outlook Data File".
  • Close MS Outlook and Repair Outlook Data File by Using "Scanpst.exe (Inbox Repair Tool)" which is a free utility developed by Microsoft.