I am not usually one to complain but Virgin Mail has been struggling for a while now.
It sometimes takes ages to initially load up the emails
When forwarding an email it is sometimes greyed out and unable to enter an email address to forward it to.
And similarly it just comes up with a blank page to forward
While going through emails to read and/or delete them new emails are loaded at the bottom of the page and the cursor goes down to them so if you are on a deleting spree you inadvertantly delete a new email, then the new emails go to the top of the page and you don't know where you are.
Apart from that everything is fine - the billing process is working fine
Been finding the same problem for last 2/3 weeks. Exactly as you describe is the issue when you want to forward anything. Takes ages to be able to do so.
I set up a new email account with Outlook.com a little while ago and I set up my @ntlworld account to forward everything to that. You never have a problem with it once it's on Outlook. I also have a Gmail account and that is never a problem. Suspect there is an answer in there somewhere. They are also both very good with the bills - they don't send you any!