My wife's computer had some issues so I decided to do a fresh install of Linux mint XFCE 20.3, I've installed linux many times on various devices & installation is usually from 20 to 40 mins, this time after nearly 2 hours it still had not finished, I was about to give but I left it while I prepared dinner, after a total of about 4 hours I checked the pc & it had now completed, so I rebooted & attempted to install the 22 updates that were available, it said "would you like to change to a local mirror" which of course I did so I opened software sources & tried to change main & base mirrors (one at a time) there was a delay of nearly ten mins before the list of mirrors opened, the 3 UK mirrors were at the top, all others said unreachable, I selected one of the UK mirrors, it told me to update the cache, there was a further delay of about 10 to 15 mins, finally it said unable to update, check your internet connection, however the internet was fine, I could use a browser & access any site, I tried to proceed with the 22 updates but after another delay a message said your cache is corrupted.
I am wondering if this could indicate a failing hard drive. Not sure where to go with this now, anyone with previous knowledge of this issue please?
I would be grateful for any advice. Thank you.

What are the precise error messages you get?

Have you tried running these commands?

The extraordinary long install time would be an indicator that there is a problem, and I personally probably wouldn't consider it to be a valid install.

Did you verify the OS iso before burning to USB? It could also be a dying USB stick.

It could be an issue with the hard drive, or perhaps RAM. I like to use https://www.memtest86.com/ for RAM verification.

Could be an issue with the specific kernel version. Have you tried a different distro?

Hi,
Firstly thanks for the replies, I'm sorry I have taken a while to come back but I've had a few problems to deal with, thankfully all sorted now.

I did try autoclean & auto remove & I did verify the ISO, further investigation seems to indicate it is almost certainly a defective hard drive so I have ordered a new one & will install Mint again when It's installed.

I am very very grateful for your assistance & will mark this thread as solved.