Gallery Not Found - But Only On Pc! Found On Phone!

I have a client who encountered a 'gallery not found' message when attempting to access from her PC. 

When she tried from her phone, she could access.

What advice can I give her to resolve the issue on her PC? She tried 2 different browsers, although I'm not sure which. 

Firewall block? antivirus block? anything else?

We both ensured she was using the correct code as we went through it together in a call.

Curiously, a different code for a different gallery (gallery passcode) did work for her on her PC a week ago, but this particular code is a consistent 'no'. (It's the old style passcode: CNR-******-.jpg) 

I can't think of any reason for it to work on one device and not the other. It is all the same no matter the device. 

Does the passcode work for you on your computer?

Odd isn't it!

Yes, works on my PC.

I'm wondering if this client is using some kind of antivirus/malware package which hasn't updated since a historic issue with Hostpapa. Many months ago, Hostpapa servers were blocked by Malwarebytes. Once Hostpapa removed offending websites, Malwarebytes reinstated them. I think it's unlikely, because the entire website would be unreachable - they can access the 'findmyphotos' page.

A mystery...

Maybe she is entering in the passcode in the wrong place on the PC? I really have no idea.

At least I can tell her there are no problems at our end, and no suggested reasons from the software developers..

Many thanks