Random Tech

In the maintenance manual, it is said:

Deleting the Password

For security reasons, the Password Deletion Disk will not be distributed to Service Providers. You
must obtain the current password from the computer's owner to service the machine.
If the owner forgets the password, contact your Toshiba representative for further action.

Means there is a way to remove the password with a special floppy disk. Digging further, there are indeed ways to remove passwords on very old and very very very old Toshiba laptops. Of course one challenge is to make sure the floppy drive works... On those old laptops, drive belts have most likely disintegrated. But first let's see what the disk should be like... This is a copy of the article in case the original website goes down:

This method works on ancient models (386 and 486 vintage probably.) This is what you need:

1. Your notebook
2. An empty formatted diskette (720 kb or 1,44 mb)
3. A second computer (e.g. a DOS desktop PC)
4. A hex-editor (e.g. Norton DiskEdit or HexWorks)

This is what you have to do:

1. Start the desktop PC and start the hex-editor
2. Put the disk in drive A:
3. Change the first five bytes of sector 2 (boot sector is sector 1) to: 4B 45 59 00 00
4. Save it! Now you have a KEYDISK
5. Remove the disk from drive A:
6. Put the disk in the notebook drive
7. Start the notebook in Boot Mode (push the reset button)
8. Press Enter when asked for Password:
9. You will be asked to Set Password again. Press Y and Enter.
10. You now see the BIOS configuration where you can set a new password.

This, unfortunately, doesn't seem to work. At no point in time does the PC triggers the floppy drive, meaning the procedure might not work for the 4500 family. Toshiba 4500, 4600, 4700, 4800, 4900 models are actually rebadged Compal computers.

I went as far as upgrading the EEPROM that has the ROM code, but it didn't change anything.

Pressing the F12 key does trigger a diagnostic screen of sort, which asks for a "maintenance disk", and triggers floppy disk activity. However, this doesn't seem to work either (tried with several floppy drives with 26 pins headers and also with a flashfloppy slim gotek) -> dead end.

I know think the "security chip" which I couldn't even identify needs to be replaced, as stated here. This seems to be confirmed on some russian forums, from which I extracted the following matrix

1. Security Chip (EEPROM): This method requires the laptop to be opened. The EEPROM must be read and modified using specialized software. This approach is suitable for specific laptop series and requires technical knowledge and experience. Any mistakes in this process can result in the laptop failing to boot.

2. PC Card Method: This involves using a key in the form of a PCMCIA card, which is a thin type compatible with LPT. It works with most laptops, but not all PCMCIA cards are suitable for this purpose.

3. Challenge Code Method: This method involves using a key combination to generate a service code that is sent to Toshiba. The manufacturer responds with another service code.

4. LPT Key Method: This method utilizes an LPT key designed according to a specific schematic. It is effective for removing passwords only on processors P1 and P2, while P3 may work only in rare cases.

5. FDD Disk Method: This method involves using a disk created on any computer, but it only works with specific processor models, namely P1 and P2.

6. USB Key Method: This key is not manufactured independently. According to the manufacturer, it can remove passwords from all Toshiba models, but in practice, it has only been effective for a limited number of series.