Here is helpful information regarding the "LSW3" firmware.
If your LSW3 switch is malfunctioning, a firmware update will not fix it. Try these free hardware solutions instead:
A: Contact Siemens support directly. By law (in the EU and US), they must provide firmware updates for discontinued products for a "reasonable period" (usually 10 years). Use the phrase "firmware for repair purposes." lsw3 firmware free
A: Absolutely not. Flashing the wrong firmware will permanently brick your controller. The "3" in LSW3 often denotes a specific hardware revision level.
For legacy LSW3 firmware from the 1990s or early 2000s that Siemens has delisted, the Internet Archive is a surprising resource. Several engineers have uploaded obsolete firmware packages as "abandonware." Here is helpful information regarding the "LSW3" firmware
Warning: Only use this for offline, air-gapped machines. Verify hash checksums if available.
If the web interface method doesn't work or isn't available, Buffalo might provide instructions for a manual update, often involving: Power Cycle: Unplug the switch for 30 seconds,
Preparing a USB Drive: Formatting a USB drive (usually FAT16 or FAT32) and placing the firmware file on it.
Inserting the USB Drive: Plugging the USB drive into the NAS.
Booting into Update Mode: There might be a specific process to boot the NAS into update mode (check the manual or Buffalo's support resources).
Automatic Update: The NAS might automatically detect the firmware file on the USB drive and update.