Written for Synergy 3 (v3.7.2), checked 3 October 2026.
When there's something to do about your license, Synergy 3 shows a message instead of the settings. Most have an Apply new license button: click it, then log in or enter your new serial key. For the steps, see: Enter or change your serial key in Synergy 3
Your license will expire on a date
Renew before then to avoid an interruption, then click Apply new license if you got a new serial key. Click Continue to keep using Synergy 3 for now.
Your license expired on a date
Renew your license, then click Apply new license. Synergy 3 can't be used until you do.
Your maintenance period will expire, or expired, on a date
Synergy 3 keeps working: click Continue. Renewing your maintenance period keeps you getting updates and technical support. More about maintenance: Access Pass (Maintenance License)
Your license is invalid
Click Apply new license and enter a valid serial key from your account page.
Your license couldn't be activated
The message explains why, and may show a License reference to quote if you contact us. Check your license and serial key on your account page. If you've reached your activation limit, deactivate a computer you no longer use or ask us to raise the limit: How license activation works in Synergy 1 and Synergy 3
Click Continue to close the message for now.
Your license needs to be activated on this computer
This appears with an offline serial key. Enter the Activation code on your account page from any device with internet access, then type the Response code you get back and click Activate. For the full steps, see: How license activation works in Synergy 1 and Synergy 3
Need help with any of these? Click Contact tech support on the message, or: Contact Synergy Support