Many thanks MHC. The test using Task Manager is brilliant! I'll try that tomorrow when I'm at my friend's again.

In reply to a post by MHC:

Accessing webmail should not have compromised your connection even if your password was hacked. It would be almost impossible to match your email address to a specific IP address for your house.

On second thoughts re the security of a BT Internet email address, the Username is shown and, of course, the ISP. So surely a Hacker only requires the password to access the Account?

Regards....

Yes, they can access the account but how would they create any traffic on the connection?

Picasa is a cloud based storage system ran by Google, so probably were the data was used.

In reply to a post by MHC:

Yes, they can access the account but how would they create any traffic on the connection?

I see, MHC, thank you so much for your help and patience.

I think it is now fairly obvious that the problem was generated by the use of Picasa. I will verify using your suggested Task Manager tomorrow.

Regards...

In reply to a post by MrSaffron:

Picasa is a cloud based storage system ran by Google, so probably were the data was used.

Many thanks, MrSaffron, It is fairly clear that the high usage was incurred by the images and Picasa, perhaps accompanied by some ignorance of the facts!

I use Lightroom and Photoshop, so I was unaware that, using Picasa, the downloading of images to the PC incurred the uploading of them to Picasa!

Regards.....

Is this the Picasa auto-backup/upload we're talking about?

I've just gone into Picasa, don't use it very often and let it update itself. After which it asked me about backing up. I said not now but browsing the various menus I can find no way of telling it never.

So will it continue to pester me?

In reply to a post by cheshire_man:

So will it continue to pester me?

Only if its logged into a Google account.

I use Picasa but have never logged into a Google account within the program, so all the online libraries and upload options are greyed out.

In reply to a post by cheshire_man:

Is this the Picasa auto-backup/upload we're talking about?

I'm very sorry Cheshire Man, I'm obviously not a Picasa user, although I know it's a favoured program. Perhaps your query should be addressed to the Picasa Forum. You can Google it!

Regards