It would also be helpful to know whether it is a single-user or concurrent-use/(floating) license. If concurrent, it may be a matter of reprinting to the license manager. It would also be good to know what the upgrade was (upgrade to win10? Patches? iE? Virusprotector? Network software? Other?
If single-user license, check out How to Deauthorize single use license, don't know ESU numbers for information about the various license codes. It may take a call to your service rep or local distributor if you cannot recover the license.
Also single use license on two machines for an interesting thread about the different types of non concurrent use licenses and what is permitted (older data but there are links.)
edit... Meant to tag V Stuart Foote who is very knowledgable about the Ina and out of licensing.
