If you are trying to upload the blob data via direct query (i.e. from a backup), the only way to reliably do it is from your shell command line, as php corrupts the binary for some reason. I've found that just not adding the attachments is the easiest way to upgrade. Although you lose the attachments, you lose alot less hair

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If you don't have shell access then yer pretty much screwed, cus even phpmyadmin won't do the attachments backup correctly.