CheckcraftPostman not working or not opening: causes and fixes
First work out what exactly broke: the app, signing in, requests or access to collections. Each has its own cause, and reinstalling does not always help.
Check whether Postman itself is down
Postman publishes the state of its services at status.postman.com. If sign-in, sync or cloud features stopped working for many people at once, the problem is on the service side and you have to wait for a fix.
You cannot sign in
You do not need to sign in to send requests: the desktop app works without an account as the lightweight API Client. If Postman says “Sorry, your access is blocked”, Postman help explains that services are suspended because of unpaid invoices. Pay them under Billing and the plan is restored.
Team collections disappeared
Since March 2026 the Postman Free plan is for a single user. If your collections lived in a shared team workspace, working on them together needs a paid plan. To stop depending on the cloud, export important collections to JSON files, as described in the export guide.
Requests to internal addresses fail
The Postman web version runs in a browser, so it sends requests to localhost and internal networks through Postman Agent, a separate program on your computer. Without the Agent these requests fail, as do requests the browser blocks under CORS rules. The desktop app does not need the Agent.
The app does not start
Go through these steps in order. 1. Force close Postman: on Windows open Task Manager (Ctrl+Shift+Esc), end every Postman process, then start the app again. 2. If the window opens but hangs, stays blank or shows glitches, choose Help, Clear Cache and Reload, and for rendering glitches Help, Disable Hardware Acceleration, then restart Postman. 3. If the window opens but cannot reach Postman servers, turn off your VPN or proxy or try another network. 4. Download the installer again from postman.com/downloads: copies in software catalogs can be outdated. Windows builds exist only for 64-bit Intel and ARM processors. On Linux, Postman recommends Snap because the package includes the libraries it needs. 5. If nothing helps, open View, Developer, View Logs in Explorer: Postman asks you to attach this log file to a support request. If the app fails only on your office network, check the proxy and traffic filtering with your administrator.
Does Postman work in Russia
We found no official Postman statement about blocking users in Russia. If the site or sign-in fails only from your network, check the service status and your company network rules first. If you need an app that does not depend on an account or cloud, Checkcraft downloads without sign-up, runs on Windows and Linux and keeps checks on your computer.
Repeat this on your own API
Checkcraft is a desktop app that saves API response checks without code and shows what did not match. Start with a sample, then use your own sanitized data. Free runs on Windows and Linux with no time limit.
Download FreeDownload and first runNo sign-up or email needed, the archive is ready in a couple of minutes. See the edition limits.
References
Postman service status · Postman help: Sorry, your access is blocked · Postman downloads · Postman help: troubleshooting app issues
Start with the linked example and compare its result with your own test requirement.