The problem seems to be related to the 3.7 setup on your end.
Is the 3.7 project standard edition? The migration tool supports only migration from Sitefinity 3.7 SP4 standard edition / community edition. The build version of the project should be Sitefinity_3_7_2136
. To check the build version refer to the following KB article
I would like to recommend you to check the special article
we have on our blogs section, regarding the migration process:
Please let us know if you have encounter anymore issues.
the Telerik team
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