Task Sequence has failed with error code 0x800700A1 "Use Toolkit Package"

Hi, @Boopathi Subramaniam
Thank you for posting in Microsoft Q&A forum.

The error 0x800700A1 translates "The specified path is invalid."
The reason you get this error is if the task sequence cannot find the path because the drive is RAW. In this case, it’s always recommended to format the disk partition before deploying Windows Image to help us avoid unwanted issues.

You may try to format the disk partition follow this article:
https://www.anoopcnair.com/sccm-task-sequence-has-failed-with-the-error-code-0x800700a1/
(Please note: Information posted in the given link is hosted by a third party. Microsoft does not guarantee the accuracy and effectiveness of information.)

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Not sure if this helps, but sometimes you cannot reach the disk due to a driver issue. Could be nothing more than a swap from RAID to AHCI. Most of the time you will find that AHCI works consistently.