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Import Outlook PST to Thunderbird
If you are running Outlook and Thunderbird on the same machine, then you can easily import Outlook mails to Thunderbird. Just follow the steps given below:
Step 1: Make Outlook your default program for sending/receiving emails. Go to the Start button and click Default Programs >> Set your default programs.
Step 2: Select Outlook from the Programs tab and click Set this program as default. Then click OK to save the changes.
Step 3: Now, launch Thunderbird and click on the Display the Thunderbird Menu option.
Step 4: Go to Tools >> Import.
Step 5: Select Mail, or you can select the Import Everything option and click Next.
Step 6: Select Outlook as the file type and click Next.
Step 7: In the last window, click on the Finish button to complete the import process.