Network Upload Method to Import PST File to Office 365 Mailbox

Himanshu Goyal Himanshu Goyal Updated On - 24 Oct 2019

Importing PST to Office 365 can be tricky if you’re not using the right approach. Though Microsoft offers two different methods to import PST to Office 365.

  1. Network Upload Method
  2. Drive shipping method

Implementing both of them is a bit complicated. Amongst the two methods, the Network Upload method is widely used by organizations to import PST data to Office 365.

Here, we will be discussing the Network upload method to import PST to Office 365 mailboxes. But, before proceeding to that, let’s highlight some essential points to execute the process.

Things to know before using Network Upload method

  • You must be assigned with Mailbox Import/Export role in the Exchange Online to import PST to Office 365
  • You must have global administrator privileges of Office 365 for your organization
  • Every manual method to import PST to Office 365 requires installation of the Azure AzCopy tool
  • You will have to store PST files on a file server or shared folder in your organization
  • By default, the maximum size of the message that can be received by Office 365 is 35 MB

Now, let’s move to the working process of the Network Upload method to import PST to Office 365 mailboxes.

Using Network Upload Method

The process of using Network Upload method involves multiple steps. Each of these steps performs a separate task that is required to import PST to Office 365. The steps that we will be covering involves:

Note: *The first step will be performed only once to import PST files to Office 365 mailboxes. After that, you have to perform step 2 to step 6 every time you want to import PST to Office 365 mailboxes.

Step 1: Copying SAS URL & Installing Azure AzCopy

First, you’ll have to download and install the Azure AzCopy tool on your system, which will be used in the next step to upload PST. Also, you’ll have to copy the SAS URL for your organization.
Note: SAS URL is the combination of network URL for the Azure storage location and a Shared Access Signature key that provides the permissions to import PST files to Azure storage location.
For downloading and installing the Azure AzCopy tool and copy the SAS URL, follow the below steps:

  1. Visit and sign in to Office 365 administrator account for your organization.
  2. Look for Security and Compliance Center in the left pane and click Data governance >> Import.
  3. As the Import page appears on the screen, click Import PST files, and then select +New import job.
  4. Now, type a name for the PST import job and click Next. Make sure you use lowercase letters, hyphens, numbers, and underscores because using uppercase letters.
  5. From the Choose import job type page, select Upload your data and then click Next.
  6. The Import Data page will appear on the screen, do the following things – copy the secure storage key, and download the Azure AzCopy tool; a pop-up window will appear on the screen, click RUN to install AzCopy.

Step 2: Uploading PST file to Office 365

Now, you need to upload PST files to Azure storage location in Microsoft cloud with the help of Azure AzCopy tool. To do this, follow the below steps:

  1. Open the command prompt on your system.
  2. Go to the directory where Azure AzCopy tool is installed.
  3. Run the below command to upload the PST files to Office 365:
    AzCopy.exe /Source:<Location of PST files> /Dest:<SAS URL> /V:<Log file location> /Y

    Here, we have used the parameters to describe the command like Source specifies the source directory where PST file is stored, Dest specifies the SAS URL that you obtained in Step 1, etc.

  4. Running the command will display the status message of uploading PST file in progress. A final status message will display the total number of files uploaded to Azure storage location.

If you want to check the list of the PST files uploaded to the Azure blob, then you can use the open-source Microsoft Azure Storage Explorer tool.

Step 3: Creating the PST Import mapping file

After uploading the PST file to Azure storage location, you need to create a CSV file to specify the user mailboxes where PST files will be imported. This CSV file will be submitted after creating a PST import job. To create a PST import mapping file, follow the below steps:

  1. Download a sample of the PST Import mapping file.
  2. Save the CSV file on your system and use Microsoft Excel to edit this file according to your requirements.

Note: A CSV file must include the following parameters:


Step 4: Creating a PST Import job in Office 365

After creating a mapping file, you need to create a PST Import job in Office 365. Follow the same steps, as mentioned in Step 1 to create a PST Import job. And when the Import Data page appears on the screen, perform the steps as mentioned in the below pictures and click Next.

  • In the new wizard, upload the CSV mapping file that you created in Step 3. After uploading the CSV file, click Validate to verify the file for any error. Once it is validated, click the Save button to submit the job, and then click Close.
  • The status page will appear on the screen displaying Analysis in Progress, and the New Import job will display in the Import page list. To refresh the status of the Import Job, you can click the Refresh button. Once the analysis is complete, the status will change to Analysis Completed.

Step 5: Filtering data and running the PST import job

When the data is ready to import, you can select whether you want to import the entire data or apply specific filters to trim the data. To do so, follow the below steps:

  1. Go to the Import Page where the import job is displayed and click Ready to import to Office 365.
  2. A flyout page will appear on the screen with the information about PST files, click Import to Office 365 on that page.
  3. The Filter your data wizard will pop-up on the screen, here select whether you want to Import the entire data or Filter it before importing. If you wish to filter the data, then check how to filter data when importing PST files. Make your selection and click Next.
  4. If you choose to import the entire data, click Import Data to start the import job. Click Refresh to update the status of the import job. When the import job is finished, the job status will change to Complete.

All your PST files will be imported to Office 365 mailboxes; you check the files by opening Office 365 account.


Network Upload is one of the most useful techniques to import PST to Office 365 mailboxes. But, as you might have observed that it is very complex, especially for beginners. So, you can use Kernel Import PST to Office 365 tool, which is a better alternative to it for importing PST files to Office 365. This software comes with advanced filters and functionalities that allow you to import PST to Office 365 based on your requirements.

Video Presentation About How Network Upload Method Works