If the device is linked to a Google account and has internet access, you can remotely erase it via the Google Find My Device portal.
In the Flashtool installation folder, locate and run the Drivers installer. Ensure you select "Flashmode" and "Xperia C" drivers. Download C2305 Xperia lock remove ftf
For those looking to bypass a forgotten pattern or PIN on the Sony Xperia C (C2305) If the device is linked to a Google
Secure the Flashtool software and the specific FTF file for the Xperia C C2305 Go to product viewer dialog for this item. . For those looking to bypass a forgotten pattern
An FTF file is a packaged firmware image specifically for Sony Xperia devices. When you use Flashtool to flash this file, it essentially overwrites the existing system software, which effectively removes user-set locks like patterns and PINs.
Move your downloaded FTF file into the firmwares folder inside the Flashtool directory. Flash Mode: Turn off your device