When you try to register a serial number to your account, you get a message:
"The old-style serial number is invalid, or has already been converted to a new-style license.
To use the license, you must sign into the account into which the serial number was converted."
This could mean that, in fact, the serial number is invalid (most likely entered incorrectly), but it could also mean that the serial number is already registered to an account. In come cases, the serial number is automatically entered to your account. (This may be pulled from the registry when updating from an older version of the program, or registered to the account on purchase.)To check if the serial number is in the account, go to HELP > LICENSE MANAGEMENT > ONLINE INFO > HISTORY. Scroll down to MY RESOURCES. Do you see activations in the account like those shown below?

If the activations are present, your serial number is registered. To activate a resouce on the current computer, simply click on the resource name and click the ACTIVATE button at the bottom.
If there are no resources, please verify the serial number and contact tech support.
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