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Fix SPA500 Series SOS Mode Recovery


Article ID:5856

Fix SPA500 Series SOS Mode Recovery


The SPA500 Series phone goes to SOS Mode Recovery state when the firmware on the phone is damaged. This is typically caused by abnormal operation such as a power interruption while the phone is upgrading. SOS Mode Recovery is manifested by an S.O.S. PhoneInRecoveryMode message on the screen of the phone after it boots up. This can be fixed by recovering the firmware using the firmware recovery tool, and loading a new firmware to the phone.

This article aims to show you how to fix a SPA500 Series phone from the SOS Mode Recovery state.

Applicable Devices

  • SPA500 Series

Software Version

  • All

Recover a SPA500 Series Phone

Note: This article assumes that the phone is in the same IP segment as the computer used to recover the phone, as it should be. The device used in this article is a SPA504G.

Step 1. Download the latest firmware for your phone from the Cisco Download Software site.

Note: In this example, firmware version 7.4.9a is chosen.

Step 2. Extract the downloaded file.

Step 3. Double-click the firmware recovery tool.

Step 4. Click Recover Firmware when the Cisco SPA Device Firmware Upgrade Utility window appears.

Step 5. Enter 12 Fs in the Enter the serial number of your SPA field.

Step 6. Verify that the auto-displayed IP address shown in the Your IP Address field is the same with the IP address of your computer.

Note: In this example, the IP Address is

Step 7. Click Continue.

Step 8. Click Upgrade.

Step 9. Wait while the upgrade is in progress then click OK as soon as the firmware upgrade is done.

Step 10. Check that the phone is booted up completely.

Note: You can perform diagnostics on the phone at this point.

You should now have recovered the SPA500 Series Phone from SOS Recovery Mode.

Download the latest firmware for your phone
WRONG advice. Firmware version must follow version of internal recovery loader. If loader version is 7.5.2b or older, even the firmware used for recovery needs to be 7.5.2b or older. No way to recover with latest (e.g. newer than 7.5.2.b) on it.
For loader version newer than 7.5.2b the firmware used for recovery needs to be 7.5.2b or newer.