If a message is blocked due to "User level block list in force" was that because a user blocked it and it was added to their blocked list?
Your assumption is correct - "User level block list in force" indicates that this user has the sending email address listed as Blocked in their Managed Senders.
The user can correct this on their own by going to Managed Senders from the Personal Portal under Advanced, or the Managed Senders button in the Outlook Plugin and then choosing to remove the block.
You can also remove this yourself from the Admin Console by going to Administration>Gateway>Managed Senders and then searching for the addresses in question. From here, you can either simply delete the block entry, or choose to specifically permit the sender, which will allow spam scanning to be bypassed.
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