If you need to password protect folders within Outlook this can be done a number of ways, probably the easiest would be to keep everything within your mailbox, so then it’s stored on the server.
The downside of this can mean huge mailbox sizes and many system administrators do impose mailbox size restrictions.
The next way is to create a PST or personal folder, this enables us to store files within Outlook, but do not count as part of the mailbox size, as they are actually separate folders.
Generally the mailbox itself will be secure, but the personal folders unless password protected can be copied and opened by anyone with a compatible version of Outlook.
Setting up a PST Password
Launch Outlook, select the File menu > Data File Management, select the PST / data file you wish to protect and select Settings > Change Password > setup a new password. Now bare in mind you’ll be prompted for the password each time you login to Outlook, unless you use the “Save this password in your password list” option.
If you need to setup a PST / personal folder read our article on this
Once this is done give some thought to these several factors
Where the PST is located backed up?
If you are storing it locally what happens if you computer develops a hard disk problem, so make sure they are stored in a location that is backed up.
Is the area where they are stored secure?
Summary
Password protect your personal folders
Make sure they are backed up
Make sure they are stored in a secure area
Never exceed Microsoft’s specified size limitations
Search for more on how to add PST password protection in Outlook
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