# Licence: Scalpel cannot reach scalpeltrade.com > Scalpel cannot check your licence: how the 72-hour offline grace keeps you trading, what a firewall or proxy can block, and when to contact support. Source: https://scalpeltrade.com/guides/fix-licence-offline Guide 13.9, Troubleshooting. Beginner, 4 min read. Checked with Scalpel 1.12.8 on 2026-10-15. By Scalpel Team. **In short:** Scalpel checks your licence with scalpeltrade.com at every start and every 12 hours. If it cannot reach the site, it keeps running on its last good check for 72 hours, so an outage at the open never locks you out. It only stops at the licence screen when it has never checked on this computer, or the 72 hours have run out. Fix the connection to scalpeltrade.com, then click **Try again**. Each good check leaves a signed pass on your computer that is valid for 72 hours from that check. Without the internet, Scalpel verifies that pass offline. Your market data and orders never go through scalpeltrade.com: they go straight to TWS or IB Gateway, so a site outage does not touch your trading. ## Scalpel can't reach scalpeltrade.com to check your licence. Check your connection and try again. You see this on the licence screen when the check failed and there is no valid pass on this computer: usually the very first activation, or a check that failed after the pass was lost. *Screenshot: The licence screen when scalpeltrade.com could not be reached: the message (1) and **Try again** (2). Demo data.* ## Scalpel can't reach scalpeltrade.com and its offline period has ended. Check your connection. This one means the last good check is more than 72 hours old. At launch it shows on the licence screen. If it happens while Scalpel is already running, you get a banner instead, ending "Scalpel keeps running until you quit". Scalpel never locks you out in the middle of a session: the cockpit, your orders and your app-managed stops keep working until you close it. *Screenshot: The mid-session banner under the header. Manage licence opens your account page. Demo data.* ## See how long you have offline Open **Settings** (`Ctrl`+`,`) and pick **About**. Under **Licence**, a normal check reads "Licensed (SCLP-\*\*\*\*-\*\*\*\*-\*\*\*\*-W8RB)." An offline one adds how long is left: *Screenshot: Settings, About: the licence checked offline, with two days left to reach scalpeltrade.com. Demo data.* ## Fix the connection ### 1. Open scalpeltrade.com in a browser on the same computer If the page does not load, the computer has no internet or something blocks the site. Fix that first. If it loads, the block is specific to the app: carry on. ### 2. Allow Scalpel through your firewall or security software Scalpel talks to scalpeltrade.com over HTTPS (port 443). A firewall rule, an antivirus "web shield" that inspects HTTPS, a work proxy or a VPN that blocks unknown apps can all stop the check. Allow the Scalpel program, or try once with the VPN off. ### 3. Check the computer's date and time The 72-hour pass is checked against your computer's clock. A clock that is days out can make a good pass look expired. Set the time automatically in Windows (Settings > Time and language) or macOS (System Settings > General > Date and time). ### 4. Click Try again On the licence screen, click **Try again**. A good check unlocks the cockpit and renews the pass for another 72 hours. **Tip.** Going somewhere with no internet? Start Scalpel once while you are online. That check gives you 72 hours of offline use from that moment. ## What can go wrong - **The site itself is down.** Rare, and the 72-hour pass covers it. If you are at the licence screen anyway, check our Discord for a status note ([guide 12.6](https://scalpeltrade.com/guides/discord-support)). - **A different message on the same screen.** "This licence is already active on 2 machines" is the machine limit ([guide 13.8](https://scalpeltrade.com/guides/fix-licence-machine-limit)). "That licence key was not found" means the key is wrong: copy it from your account page ([guide 1.3](https://scalpeltrade.com/guides/activate-licence)). - **"The licence server sent a token this build can't verify. Update Scalpel."** Your copy is too old for the server. Download the current version from scalpeltrade.com/download. ## Questions **How long can Scalpel run without internet?** 72 hours from its last successful licence check. Every start and every 12 hours online renews it. **Will Scalpel lock me out in the middle of a trade?** No. A licence problem found while Scalpel is running only shows a banner. It is enforced at the next start, and the licence screen still offers Flatten all if anything is open. **Does my trading go through scalpeltrade.com?** No. Market data and orders go between Scalpel and your own TWS or IB Gateway. scalpeltrade.com only checks the licence and offers updates. **Which address does the licence check use?** https://scalpeltrade.com over port 443. Allow it in your firewall, proxy or security software.