I notice a couple of posters have mentioned receiving the same (I assume) Bitcoin $500 demand email over recent days (I had received 6 emails since 3rd June, some with different Bitcoin numbers, before my email access has been blocked), quoting my NTLWorld email address and password in the body of the email. @tonyplant mentioned this issue in his post this afternoon (https://community.virginmedia.com/t5/Email/how-do-i-delete-an-old-ntl-acount/td-p/5032909). The email appears to come from your own NTLWorld account.
I have requested support on another thread to resolve my issue (https://community.virginmedia.com/t5/Email/Migrate-and-Switch/td-p/5032178), as I cannot access my account to change the password (I am patiently waiting for help from Mods, as I originally raised my issue on Sunday - any help would be appreciated if they happen to see this).
I am posting here as a separate thread to see if others have received the Bitcoin demand emails with subject "ALERT! Im hacked your computer and stolen your personal data and photo!" and if it is therefore a wider security issue on NTLWorld/Virgin Media servers since 3rd June or just coincidence? By posting it on here I am also trying to reassure anyone else that has received this email that it is a SCAM, no doubt sent to a lot of people at the same time.
It would be worth people checking their email/password for security breaches (iPhone and Google may flag any password issues, there are pwned websites which let you check too) and ensuring any passwords are unique for any site you use (I know, great advice - I am now working through changing other passwords to be on the safe side). If you are able to do so, change your NTLWorld email password anyway (though I note a few people are having issues doing that at the moment).
I hope this helps.