Migrate from ANSI to Unicode

Sadly there is no convert or upgrade option which automatically changes a pst-file from ANSI format to Unicode format. Also upgrading your Outlook version doesn't change the format of your pst-file.

You can however migrate your data from an ANSI pst-file into a new Unicode pst-file.

Step 1: The conversion process

So, after you have determined that your pst-file is in ANSI or Unicode format and you want to convert your ANSI formatted pst-file to Unicode, you must do this manually. While the process is quite easy, it is tedious though, especially if you have a large pst-file and lots of folders directly below the root folder.

1. To be safe, make a backup of your pst-file that you want to convert first.
2. Create a new pst-file by;
   • Outlook 2003 and Outlook 2007
     File-> New-> Outlook Data File...
   • Outlook 2010, Outlook 2013 and Outlook 2016
     Home tab-> button New Items-> More Items-> Outlook Data File…
3. When prompted (Outlook 2003 and 2007 only), select "Office Outlook Personal Folders File (.pst)" and press OK
4. Accept the default file name and location or change them as you please.
   • Personally, I prefer to keep my pst-files in the (My) Documents folder where I have a folder called Outlook. I usually name my pst-files after the account name for which I'm going to store the messages in. Example;
     D:\Users\Robert\Documents\Outlook\msoutlook.pst
5. When using Outlook 2003 or 2007, a new dialog pops up where you can specify the display name, encryption settings (not recommended unless you have a very specific need to do so) and optionally set a password on the pst-file.
6. Switch to the Folder List Navigation (CTRL+6). This will make it easier to also copy your Calendar, Contacts, Journal Tasks and Notes folders.
7. Now copy all the folders from the ANSI pst-file to the newly created Unicode pst-file.
   • You can do this by drag & drop but since the default drag & drop with the left mouse button is a "Move" action instead of a "Copy" action you must use drag & drop with the right mouse button. Now when you drop the folder, you’ll get a pop-up menu allowing you to choose to Copy the folder.
   • This copy action also copies all the subfolders.

Note 1: Depending on the size and the amount of folders and items in your pst-file, this copy action can take quite a while. During this, Outlook may appear to be in a non-responsive state while in fact it is not. A good way to see if Outlook really is not responding anymore is by going to the location where store your newly created Unicode pst-file. Look at the file size and refresh your view every few minutes by pressing F5. If it is still increasing, Outlook is still running as it should.

Note 2: If your ANSI pst-file doesn’t display the correct characters (for instance Cyrillic letters), moving them to a Unicode pst-file will not make them appear correctly either. To solve this, you may need to install the correct Windows language pack first and try importing the pst-file instead. If this fails too, contact Microsoft Support.

Step 2: Deliver emails to your new Unicode pst-file

If you want your new emails delivered to this newly created Unicode pst-file you must set it as the default delivery location. To do this;

• Outlook 2010, Outlook 2013 and Outlook 2016
  File-> Info-> Account Settings-> Account Settings…-> tab Data Files-> select your newly created pst-file-> button "Set as Default"-> button "Close"-> Restart Outlook
• Outlook 2007
  File-> Data File Management...-> select your newly created pst-file-> button "Set as Default"-> button "Close"-> Restart Outlook
• Outlook 2003
  Tools-> Email Accounts...-> Next-> use the dropdown list below "Deliver new e-mail to the following location:" to select your newly created pst-file-> button "Finish"-> Restart Outlook

When you are using Outlook 2007 or later, after restarting Outlook, verify that all your accounts are no longer set to delivery to your ANSI pst-file;

1. Open your Account Settings dialog
   File-> Info-> Account Settings-> Account Settings…-> tab E-mail
2. Select each POP3 account and look at the delivery location at the bottom of the dialog.
3. When this delivery location is still set to your ANSI pst-file, press the Change Folder button to set it to your Unicode pst-file.

Step 3: Disconnect the ANSI pst-file

Now that everything has been converted and configured properly, you can disconnect the ANSI formatted pst-file from Outlook. You can do this by selecting the file in the data files overview of Outlook and pressing the Remove button.

• Outlook 2010, Outlook 2013 and Outlook 2016
  File-> Info-> Account Settings-> Account Settings…-> tab Data Files-> select your ANSI pst-file-> button Remove
• Outlook 2007 and Outlook 2003
  File-> Data File Management...-> select your ANSI pst-file-> button Remove

When you now close Outlook, you can actually delete the old ANSI formatted pst-file as well to free up some space. Do not delete the file before disconnecting it from Outlook.