Every once in a while, I have Solidworks files that refuse to be archived. The error message is that the file does not meet the conditions of a workflow when if it is in a workflow (version 12 of the file), it is because it meets the right conditions. By logging in admin, it works however the user rights are ok. Mystery of PDM. Even the support doesn't understand.
If your file is version 12, what has been its path? Has it only been archived 12 times or has it changed state (Approval, index increment ....)? Put an image of his history, it will allow you to better understand how he got there and at what point a transition condition becomes blocking.