I have uninstalled the single-user licence on my notebook, then I have uninstalled Keil MDK µVision. After a few days I installed the MDK again and got the licence via Internet. After I put the licence code into the input field, I got the message "*** ERROR R20E(1): LICENSE INVALID - TRANSFER FAILED". It means that the licence is alreadu uninstalled, but I have got the new licence at this moment. Curiously, I can repeat the procedure many times, every time I get the same licence code and everytime I get the same error message. I suppose, there is something wrong with the licensing, but there is no phone number, I could call to fix this. I would appreciate any idea to solve this baldly.
If it is about Licensing and if you already possess a valid license key, please always open a new Support Ticket:
https://www.arm.com/support/contact-support
Thank you!