When Jerry Tack received an email saying the TV licence needed paying, he didn't think twice about it.
Nothing seemed suspicious about the website he clicked on, so he entered his bank details - and began a chain of events that would lose him £9,900.
Jerry, from Hampshire, was among thousands contacted in what police called a "particularly nasty" fraud.
But the banks say they cannot reimburse customers who have mistakenly authorised payments to fraudsters.
A TV Licensing spokeswoman said: "TV Licensing will never email customers, unprompted, to ask for bank details, personal information or tell you that you may be entitled to a refund."
'We were left penniless'
Carole Tack, Jerry's wife, said that two days after filling in the fraudulent TV licence form online, he received a call purporting to be from his building society, Nationwide.
In reality, it was a scammer who had harvested the 65-year-old's details from the fake form.
The caller asked him about two fabricated transactions, and when he said he had not made them, they advised him to move his money into a "safe account".
Jerry then received a text message with a code from the building society, most likely triggered by the scammers requesting it under a system designed for people who have forgotten their log-in details.
Believing it had been sent by the person he was speaking to, he overlooked warnings not to share the code and gave it to the caller as confirmation.
That inadvertently allowed the scammers to access his account.
They emptied two savings accounts of £4,000 each and persuaded Jerry to use a card reader to approve the transfer of the funds, as well as £1,900 from his current account, telling him it would protect the money from fraudsters.
Half an hour later he had second thoughts and contacted Nationwide, to be told that he had been the victim of an "authorised push payment" (APP) scam.
"We were left penniless until the end of November," said Carole, 61. The loss of their savings put "an awful lot of strain on our relationship".
"Hubby and me fell out big time over it. I didn't speak to him for about a week," she said.
"Christmas for us was a complete wash-out. I didn't even put any decorations up - we didn't feel like it."
But while she acknowledged her husband had made a mistake, she felt financial institutions could do more to support victims of frauds such as this.
'All taken away by an email'
Laura Hodson, 27, received a similar email saying payment details for her TV licence needed to be updated.
"The site looked very realistic and I think because it was due for renewal I didn't think it was unusual. The fines are so big that to do nothing panicked me more," she said.
More than 24 hours later she received a "gut-wrenching" call from her bank, RBS, to say that more than £2,500 had been taken.
The payments were traced to a Barclays account and after about a month of wrangling Laura was told that only £2.21 could be recovered.
"We came across as a nuisance and that the scam was our entire fault," Laura said.
Laura, a nurse from Dumfries, lost the money two days after payday at the end of October, leaving her and her partner Scott struggling to make ends meet and relying on the financial support of family.
"That was all taken away by a single email," she said.
How did the banks and police respond?
Banks say that the funds in these cases are frequently transferred to accounts owned by students being used by the scammers as "money mules".
The cash is often impossible to recover because it is transferred between several accounts operated by mules in quick succession to avoid detection, before being withdrawn.
UK Finance, a banking industry group, said it was introducing a new voluntary code for members setting out "clear requirements for consumer protection and the principles for reimbursement".
But Nationwide said that Jerry Tack's funds could not be reimbursed because he had authorised the payments and ignored warnings not to share security information.
A spokesman said: "We're very sorry that our member has been a victim of this cruel scam.
"Unfortunately, despite warnings generated by our systems, the member gave away details to the fraudster and originated all of the transactions into the third-party account."
RBS has been contacted for comment.
Action Fraud, the national reporting centre for fraud and cyber-crime, said all reports of scams such as the TV licence one are sent to the National Fraud Intelligence Bureau, which assesses if there is enough information for an investigation.
Reports can also lead to telephone lines and websites used by fraudsters being shut down, or bank accounts being closed, the centre said.
A spokeswoman said: "This disruption activity prevents people being defrauded in the future and therefore making a report can help stop others from becoming victims themselves."