• Tos620a

Eventually, it was discovered that this particular device was installed as a part of the Toshiba Supervisor Password Utility. This SHOULD have resulted in a simple fix but Toshiba made this utility locked to a specific set of Serial Numbers. This meant that if your laptop had a serial number that wasn’t in this set, you were out of luck. The program would refuse to install and the driver would not load. I tried to get an image of this, but not that I have the Firmware Linkage Driver installed, I can't seem to get it to bring up an error. Thanks for posting this PedroDaGr8.I installed Windows 7 x64 late last year and like many had the same annoying 'Unknown Device'.

After spending ages doing various Google searches and contacting Toshiba I was resolved to disabling it (like you say, it doesn't 'seem' to do any harm).My Toshiba laptop came with 2GB RAM (upgradable to 4GB) and Vista x86. I went for this model as it supports 4GB but what Toshiba didn't say, was they don't provide drivers for this model for Windows x64. After sending several e-mails asking how I was supposed to get 4GB RAM with Windows x86 and getting nowhere (Toshiba didn't want to know), I gave up. Their response was that you can install 4GB RAM with Vista x86 and 'what's the problem only being able to use 3.2GB of it?' Obviously not answer I was happy with.Like you I discovered Supervisor Password Utility was the key and like you, discovered it refused to install on Windows x64 (Windows Vista x86 or Windows 7 x86 isn't a problem). I didn't know it was serial number locked though (Why?).Only the other day I finally fixed this by installing Driver Easy (drivereasy.com), which installed the Vista x64 Firmware Linkage Driver (v1.0.0.3) but downloading your link, the Windows 7 x64 driver is newer (v1.0.0.6).When installing Windows 7 x64, I literally just needed two additional chipset drivers. The Firmware Linkage Driver and a Flash Media Driver (which I managed to install the Flash Media x64 driver from another model, this time not serial number locked).It would be so easy for Toshiba to create a Windows Vista x64 subset on the download page for my model (and clearly yours too).

Tos620a

If we've worked it out, it's obvious some Toshiba technical support person knows this too!As the laptop was supplied with Vista x86, instead they flatly refused to help me. It looks like Toshiba North/South American support, are are useless as Toshiba European support.Thanks for taking the time to post this again.

Tutorial how to install Driver ACPI TOS1900 and ACPI TOS1901 on a Toshiba laptop C640 PSC36L.How to install drivers ACPI TOS1900 and ACPI TOS1901:1. Download driver ACPI TOS1900 and ACPI TOS1901Link:Password: pemudadesa2. Extract the driver.3.

Open the device manager by:Start - Control Panel - Device Manager - Unknown Device4. Right click and select 'Update Driver Software'.5. Select 'Browse my computer for driver software'.6. Point where you extract the driver that you downloaded earlier.7. Select 'Next' and wait for it to finish, then select 'Finish'.