Firmware: Vestel
Vestel provides firmware to retailers, not consumers. However, you can access their public FTP/update server via vestelpirate.net and update.vestel.com (Note: These change frequently. Use a curl command or search for "Vestel OTA server list").
Because Vestel builds for other brands, check these websites: vestel firmware
Cause: Corrupt user data partition. Fix: Perform a Forced USB Recovery. Vestel provides firmware to retailers, not consumers