Maximum File Size and Deletion for Azure Blob Storage in Microsoft 365 PST Import job

Question

Hi Community,

I'm working on a Microsoft 365 PST import workload and leveraging Azure Blob storage. Are there any limitations on the maximum size of data I can upload to the Blob storage during this process? Additionally, after the import is complete, is it possible for me to delete the uploaded PST files from Azure Blob storage myself?

1.What is the maximum azure blob storage provided at backend of Microsoft 365 pst import job?

2.Can I upload pst files into blob storage more than 4TB into import jobs.

3.Can we delete files uploaded in azure blob storage?

Please help me on these questions

Thank you!

Answer 1

Hello GARRE AKHIL,

Thank you for posting your query here!

Regarding the PST Import process, below are two official documents for reference:
Use network upload to import PST files to Office 365
FAQ about importing PST files

According to the information in these articles, we can learn that the PST files will be uploaded to a private and secure Azure Storage location that resides in the same regional Microsoft datacenter where your organization is located.

As for your concern about storage size limits, the articles above didn't mention any documented limitations as such. However, the following two things which are related to the PST file size are mentioned in the article, so it's suggested to pay attention to these limits when importing the PST files.

· For Microsoft 365 PST imports, while Azure Blob Storage itself can handle extremely large file sizes (up to 190.7 TB for block blobs), the PST import service has specific limitations to consider. It's recommended that each PST file you upload to the Azure Storage location should be no larger than 20 GB:

· If a PST file contains a mailbox item that is larger than 150 MB, the item will be skipped and not imported during the import process.
So yes, it is technically feasible to upload 4TB of PST files into Azure Blob Storage for Microsoft 365 import jobs, however, you would need to keep individual PST files under 20 GB.

Also, the PST files cannot be deleted once being uploaded to the Azure blob. This is also documented in this article:

I hope this helps! Please let me know if the issue persists or if you have any other questions.

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