If you have lost the activation key of Sage 50 software, you must be getting difficulty at the time of reinstalling or updating the software. To get the activation key back, you can follow the steps given below:
 Open Sage in the browser
 You need to provide your login credentials
 Go to ‘My accounts’ and check all of the linked accounts
 Go to ‘Products and services.’
 You would see the serial number
 Click on the required serial numbers
 You would know the activation key over there
 Note down the activation key and the serial number
If you need more assistance regarding the issue, get in touch with Sage customer support where the experts are available to help you

Solved: How do I Find My Sage 50 Lost Activation Key