Unknown device taking a license seat

I just set up my second computer with DEVONthink per this helpful thread.

When I tried to register my license, I received an error that both seats were taken. I logged in to my license account, and indeed it listed two seats used: one for my MacBook Pro, and one for an unknown device.

I was able to delete it, and register my MacBook Air, but I wonder about the second device. I’ve only ever installed DT3 on one machine (plus my iPhone).

Unfortunately, I did not screenshot it, but the device name was a random set of numbers and letters, starting with “C” (eg, something like C02HN4YU7). It said it was last used on December 07, 2020.

That date doesn’t mean anything to me. I don’t think I changed anything with DT in December (I did have some troubleshooting with DT Support in February with the new CloudKit syncing; I don’t think it’s related).

Does anyone know what the device may have been?

Please open a support ticket and we’ll help you get this resolved. Thanks.

Just to chip in here (obviously do start the support ticket as suggested by Jim): in December 2020 there were a number of posts here from users noting their licenses suddenly appeared expired. Eric explained at the time that some changes to the backend had caused some licenses to become detached. I guess that might be what happened to you too.

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Just to emphasize, I seem to have resolved it by deleting the unknown device. I was then able to register my Air.

I’m still curious / concerned about the unknown device though.

If my guess is right, then the unknown device is you with a different (now detached) name. So - says the random person on the internet - don’t be too concerned (but checking sounds like sound security advice :+1:t2:)

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Glancing at the thread you shared, I have a vague recollection of re-entering my license info per Jim’s advice. The start date of the thread (December 08) evens aligns with when my unknown device was last seen (December 07). I bet that’s the answer.

We’ll see what Support says, but I feel better for now. Thanks!

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Apple doesn’t let us get unique device identifiers (UDID)that we could use to tie your license to your device. In the past we used a different algorithm to create such a UDID and your unknown device with just a long ID as its name was one of these.

In general, removing devices from a license never cause any harm. The worst thing that can happen is that you need to enter your license code again on the affected devices.

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Here is DT Support’s response to my ticket:

“The strange registration, “C0…” was a double registration of your machine. This happened with a few clients. In the meantime, we have solved the problem. You did exactly the right thing, you deleted the duplicate registration and freed up one seat.”

All is well. Thanks for the help everyone!


Interesting. I recall this some time back when I looked at my account. I just checked and there is indeed 2 seats used for my license. I simply deleted the other one that I don’t recognize. I only use the desktop version of DT on 1 Mac. DT2Go is on an iPhone and iPad and those should be unrelated to desktop DT.