nc -zv zpj.io 8877
If it still says `Connection refused`, the server is genuinely offline on their end.
**Here's what I recommend doing right now:**
File a GitHub issue — it takes 2 minutes and is the only way to get this unblocked:
1. Go to `https://github.com/wifisensing/PicoScenes-Issue-Tracker/issues/new`
2. Title: `Port 8877 connection refused — expired build blocks USRP B210`
3. Paste this:
Build: 2025.1217.1547 (expired -31 days)
OS: Ubuntu 22.04, kernel 6.5.0-15-generic
Hardware: USRP B210, serial 312EB54, USB 3.0, detected by UHD 4.8.0
Problem: zpj.io port 8877 returns "Connection refused" from multiple
networks. Trial license activation fails. Build expiry blocks USRP
plugin — "Unresolvable device ID: usrp" on every run.
UHD detects B210 correctly:
uhd_find_devices → serial: 312EB54, product: B210 ✓
uhd_usrp_probe → Operating over USB 3. ✓
Request: Please push a new non-expired build or restore port 8877.
nc -zv zpj.io 8877
Build: 2025.1217.1547 (expired -31 days)
OS: Ubuntu 22.04, kernel 6.5.0-15-generic
Hardware: USRP B210, serial 312EB54, USB 3.0, detected by UHD 4.8.0
Problem: zpj.io port 8877 returns "Connection refused" from multiple
networks. Trial license activation fails. Build expiry blocks USRP
plugin — "Unresolvable device ID: usrp" on every run.
UHD detects B210 correctly:
uhd_find_devices → serial: 312EB54, product: B210 ✓
uhd_usrp_probe → Operating over USB 3. ✓
Request: Please push a new non-expired build or restore port 8877.