This issue can occur If you have created multiple jobs and the file downloaded does not belong to the Snowball device. Each Snowball job has its own unique manifest file and unlock-code. Please check if your job id on console matches with the name of the manifest file (e.g. JID*_manifest.bin). Also, try downloading the file from a different workstation.
The following AWS official documentation states that if you encounter problems with the manifest file, you should re-download the file. 
 Troubleshooting AWS Snowball Edge - AWS Snowball Edge Developer Guide
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Each job has a specific manifest file associated with it. If you create multiple jobs, track which manifest is for which job.
If you lose a manifest file or if a manifest file is corrupted, you can redownload the manifest file for a specific job. You do so using the console, AWS CLI, or one of the AWS APIs.
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We hope the above is helpful.
Yes, that's correct, but the file is not correupted. I tried to re-download it to be sure, but it didn't solve the problem. I am still getting the same error
Thanks, I have only one job, so i can't mix with a different job. The manifest file was working fine before the power outage. Suspecting my windows PC, i also tried to re-download manifest+key from a linux machine and i got the same error.
Given that you've already verified the unlock code and manifest file are for the JID specified on the e-ink display, please contact AWS support via the AWS Console. Inside the console, click the question mark, then select Support Center. From there, you can create a case.
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