Untrusted Connection over VPN

[Mr Pointy]

I'm currently in one of the Arabian states & am having problems connecting to some https sites over VPN. When I try to connect I get an "Untrusted Connection" warning from Firefox. I've tried VyperVPN & Tunnelbear & via the Wifi at two sites & the wired connection at the hotel. I had thought that using a VPN would give me the ability to log on to my bank in the UK, but it seems not. I'm using Kaspersky AV.

A couple of samples of the errors I get:

bcol.barclaycard.co.uk uses an invalid security certificate.
The certificate is not trusted because the issuer certificate is unknown.
(Error code: sec_error_unknown_issuer)

www.paypal.com uses an invalid security certificate.
The certificate is not trusted because the issuer certificate is unknown.
(Error code: sec_error_unknown_issuer)

Can anyone help? Is it a result of using a VPN or some other more sinister problem?

[Mr Pointy]

I don't seem to get the errors using Chrome so maybe it is a FF issue. Thanks.

[Mr Pointy]

Apologies, I've just noticed that I haven't replied to this thread; it was indeed the Kaspersky SSL scanning that was causing the issue. I disabled it & can now pay my bills.

Thanks to all for for the help.