Can I merge .pst files from old laptop into Outlook Desktop App on new laptop?

Question

I bought a new W11Pro laptop to replace an old, slow one.

Initially, I was using Outlook webmail for my three business email addresses, all on the same domain.

I have one licensed M365 Business Standard address, and two unlicensed addresses under delegated access.

Call them ******@mydomain.com , ******@mydomain.com and ******@mydomain.com

Later, when I installed Outlook desktop app, it automatically downloaded latest emails from the M365 cloud to the laptop.

First, I noticed that there is only one Outlook Data File on the laptop, called ******@mydomain.com which I assume contains data from all three addresses merged into one file?

Second, the email data in the single file only goes back one year, but I have several years of data previous to that, which I would like to access.

I backed up three .pst files from the old laptop, named ******@mydomain.pst , ******@mydomain.pst and ******@mydomain.pst

Can I merge these three .pst files into the single new Outlook Data File?

Many Thanks

PhilRW

Answer 1

Hi @PhilRW

the email data in the single file only goes back one year, but I have several years of data previous to that, which I would like to access.

Cached Exchange Mode is the default when you add an Exchange or Microsoft 365 account. Usually, Outlook configures Exchange and Microsoft 365 accounts to only synchronize 12 months of your email under Cached Exchange Mode.

If you want to sync all emails, move the sync slider to ALL, you can refer to this link:

Control how much mail is kept offline.

Can I merge these three .pst files into the single new Outlook Data File?

In order to prevent damage to data files, it is recommended that you use hardware storage or upload files to OneDrive, and import them to Outlook365.

Import Outlook items from a .pst file in Outlook for PC

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Answer 2

Hi PhilRW,

I see that Audrey Hepburn has already provided you with an excellent method. However, if you're looking for an alternative approach to merge the .pst files into the Outlook Desktop App, you can try the following steps:

1. First, make sure to copy the .pst files (******@mydomain.pst, ******@mydomain.pst, and ******@mydomain.pst) from your old laptop to your new one.
2. Now, let's open the Outlook Desktop App on your new laptop.
3. Next, go to "Account Settings" within Outlook.
4. Here's where you'll add each .pst file individually (e.g., ******@mydomain.pst, ******@mydomain.pst, and ******@mydomain.pst) as separate data files.
5. Finally, close the Account Settings.

By following these simple steps, you'll successfully merge your .pst files into the Outlook Desktop App on your new laptop. Each .pst file will appear as a separate data file within Outlook, giving you convenient access to the email data from each of your addresses. If you have any further questions, don't hesitate to reach out.