Go to the SamFw Firmware Archive and download the official stock firmware matching your desired target CSC.
If you encounter this failure, follow these updated steps to resolve it:
→ Update to the latest version (v5.4 or v5.3). → Re‑enter Test Mode ( *#0*# ). → Reinstall Samsung USB drivers and close Smart Switch / Kies. samfw running exploit fail updated
Based on numerous forum posts, here are additional tips that have helped real users overcome the FAIL error:
Newer devices, particularly the S24 Ultra, S25, and early S26 leaks (2025/2026), have tighter security. The "Running Exploit Fail" is common here, as the exploit may only support older security patches. If you are on the absolute latest patch, you may need to wait for a SamFw Tool update. Running Exploit Fail During CSC Change Go to the SamFw Firmware Archive and download
Security software frequently flags exploit tools as false positives, blocking the scripts required to access the phone. Temporarily disable Windows Real-time Protection. Pause any third-party antivirus software.
Switch to an alternate method and click the action button again. 3. Re-enter the Test Mode Menu → Reinstall Samsung USB drivers and close Smart
If you have tried all exploit options within SamFW and still get a "FAIL" message, your device security patch is too new for the tool's current internal database. You can try these alternative methods: