USB Flash Drive Not Recognised

CSM (Compatible System Mode) is normally to install Win 7

Try to disable Secure Boot but leave as UEFI mode.

What are the specs of the Toshiba Laptop no. 3?

NavyLCDR said:

Is the USB flash drive formatted as NTFS or FAT32? It should have 1 partition on it and it should be FAT32.

To find what Navy suggest::
Open a CMD window as administrator and type:

diskpart
list disk (it will list all drives. Identify the USB drive number)
select disk n (replace n by the USB drive number obtained with list disk)
list part (is there more than one partition?)
select part 1
detail part (is it ntfs or Fat32?)
exit

Just checked the flash drive.......it is in FAT32 format.......

- - - Updated - - -

Well, it MUST be the flash drive that is at fault, although strangely it shows on the BIOS of the other three Toshiba Satellite's......currently installing W 10 on laptop No. three, using a different flash drive, and all is going well.....Thanks to all who replied......another learning curve !!......EDIT......Just two final questions, is it possible that W10 32bit will run better on older hardware, than 64bit ?.......and also, can you delete partitions on your drive AFTER installing W10 ?.......

I install Win 32 bits only if the computer has 4G or less memory and use internal graphics.
If it has more than 4G you have to use 64bits to use the memory that exceed 3.2G.

A Win 10 installed as has UEFI-GPT has the following partitions:
- EFI - Fat32 - 100M
- MSR - RAW - 16M
- C: - NTFS - large partition
- Recovery - NTFS ~650M (I've made mine 850M)

I don't recommend you delete any of them as they are linked to the OS.

Del 80 said:

Thank you......Number 3 has only 2GB of RAM, and is running 64bit......this has certainly been a learning curve !!

2 G is low even for 32 bits and 32 bits OS can only be installed as Legacy-MBR (and you did install as UEFI-GPT). To use 32bits OS you would have to change BIOS settings and reinstall Win 10 32 bits.

I suggest you buy two 4G memory sticks. Nowadays it shouldn't cost much.