Working Guide Of The MailsDaddy OST To Office 365 Tool

Uploading OST data to the Office 365 portal using Bulk Migration is extremely useful when you need to migrate one or multiple OST files into the same or different Microsoft 365 accounts at once. However, before using this advanced feature, you must assign Application Impersonation rights and Full Access permissions to the Admin account.

Step 1: Clear all selected OST files from the preview section, then click the Bulk Migration button to proceed.

Step 2: You can include all migration details in a CSV file. Download the sample CSV file and use it as a template to create your own file for OST migration.

• After updating the CSV file, click Browse CSV File to import all details into the application.



• Once you have uploaded the CSV file. It will automatically fetch the location of OST file and account details.
• Next, choose the mailbox type: Primary, In-place Archive, or Group mailbox. Then scroll to the right to optionally enter a folder name and enable or disable incremental migration. Creating folder option lets you migrate data into a new folder within the selected mailbox. At last save the destination of log file and click Next button.




Step 3: Choose the verification method: Automate or Manual. Both are safe method to verify your Office 365 account.

With manual way, you have to create: Tenant id, Client id and Secrect value by following our guide.

Step 3: Once you have verified the Microsoft 365 account. Click on Continue button.

Step 4: Now a pop-up message will be appear to guide your to click on Start button to start the process. Click OK button then press Start.

Step 5: You can see the migration is running simultaneously. Now, wait for the process to complete.

Step 6: Once the migration is done, it will automatically move to below window. That's it. You can now visit the relevant account to check your mailbox.

If you want to import emails from a specific OST file into your Office 365 account, you can use the Search option. Follow the steps below to proceed.

Step 1: On the right, select Folders and choose the desired search criteria (To, From, Subject, Date, etc.) to filter emails. Enter the details and click the Search button.

Step 2: All the filtered emails will appear below. Select the emails you want to migrate to your Office 365 account, then click the Migrate button.

Step 3: Select the target mailbox: Primary or In-place archive and enter the folder name to migrate all data in it. Click the Browse icon to choose the location for saving the log file, then click the Next button.

Step 4: Choose one method to verify the Microsoft account: Automate or Manual

With manual way, you have to create: Tenant ID, Client ID and Secret value by following our guide.

Step 5: Once you have verified the account then type target email address and click on continue button.

Step 6: You will see the migration window on the screen, wait until the migration is finished.

Step 7: Once finished, a confirmation will appear—simply click the OK button and visit the target account to check mailbox.

Migration History is an important feature that helps you track all migration activities. It allows you to verify whether all data has been successfully migrated.

Step 1: To access it, click the Migration History tab. Here, you can view the migration start date and time, NSF file names, and corresponding email addresses.

Step 2: You’ll also see the total data count, migrated data count, and counts for skipped or failed items.

Step 3: Click Open Logs to view a detailed migration report in a .txt file.

Step 4: If any items failed to migrate, you will see a Retry button. To migrate the failed items, click the same Retry button.

Step 5: Since the logging details are already entered, verify them and press the Logging button to re-migrate the failed items.