I recently had a complete system crash on my desktop PC and had to replace my motherboard and CPU. Since this my copy of Lightroom 6 is telling me that it has already been used on the maximum number of machines allowed. Other than deactivating the copy on my laptop (the second device), can anyone tell me how to get my copy to work on my rebuilt PC please?
Please refer the below troubleshooting link.
else contact the Adobe Support : Contact Customer Care
Let us know if that helps.