Yes, Third party tools are safe for Office Backup in EML files but remember to consume a better reviewed tool. I personally use
eSoftTools Webmail Backup Software for the same query. It is too good in their service. They take backup within 3 steps and give the option to save the exporting data into more than 9+ different formats. They also work on all kinds of Windows OS, Anyone can easily operate and understand its GUI, multiple email selection is available, they give you filtration features for easy selection of the Backup files. You get a 30 days money back guarantee on their service.They also give Free updates and Free Demo Trial in which you have a chance to export 20 free items.
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