Troubleshooting License Key Problems
Lost License Key
License Key Not Accepted
License keys are always valid only for a particular Citavi version. A Citavi 2 license key does not work in Citavi 3, 4, or 5. (Exception: site licenses).
Check if you're working with Citavi 5. The version number is displayed at the bottom left of the welcome screen. If you have a license key for an older version, purchase a license key for Citavi 5. If you previously purchased Citavi 3 or 4, you're entitled to an upgrade discount. You can find the discounted license by accessing the Citavi Shop from your Citavi account..
If Citavi does not accept a Citavi 5 license key, it's often due to it being copied or entered incorrectly. In your Citavi account, copy the license key to the Clipboard. Then, on the Citavi Welcome Screen, click License > Enter a license key.
If you enter a site license key and it's accepted but Citavi starts as Citavi Free, you likely have expired license keys on your computer. Check the folders "C:\Users\[your name]\AppData\Roaming\Swiss Academic Software" and "C:\Program Files (x86)\Citavi 5\bin" for files with the name "common.dat5" or "common2.dat5" (the number in the file extension can vary). Delete these files and enter your license information again.