^ This.
By far the most common reason for database import to fail, is because people tend to configure the new SMS as a seperate virtual machine, without Internet access. Which is perfectly fine, but as the new deployment is stilling with no access to updates.checkpoint.com, things like migrate_server, hcp, cpinfo etc. Is not able to automatically update.
You are most likely exporting on R81.20 Build 631 with updated migrate_server script / upgrade tools, as this installation has internet access and thus is able to auto-update these scripts in the background. While your attempt at importing on R81.20 Build 634 is most likely taking place on a virtual machine without internet access, requiring you to manually update the migrate_server / upgrade tools before importing.
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