"It feels personal."
The calls began last Monday and are understood to be part of a phone scam that has been around for about six years.
"He called and said, 'You have a Windows laptop with a virus and we need to help you fix it'."
Ms Hewetson had told the man she didn't have a Windows laptop, which seemed to enrage him. The man, who had an Indian accent and knew Ms Hewetson's name, had called back "again and again" throughout the night.
He had told Ms Hewetson he could see her on a screen.
The calls persisted on Tuesday, Wednesday and Thursday, as the man called about seven times each day.
"On Wednesday I said I'd call the police and he just jeered at me.
"It's always the same man. He's very nasty."
On Thursday night Ms Hewetson, after hanging up on the man multiple times, asked him: 'Who are you and why are you calling'?" The man had responded in an ominous voice: "I'm from the F-B-I."
"By Thursday night, I was unsettled," Ms Hewetson said. "I went to bed and his voice was in my head. I felt invaded and insecure."
Ms Hewetson dialled 111 and spoke to the police, who advised her to take her phone off the hook.
She isn't the only person in the region to receive repeated calls from a computer virus scammer.
Hawke's Bay Today received an overwhelming response via Facebook from readers who had received similar calls, often after 10pm.
"We get them up to three times a week. Last week the guy actually sang "Liar liar pants on fire" on the phone. I could not believe it."
"We get one a day for over a year."
NumberCop CEO Jan Volzke, who tracks phone scams worldwide, told Hawke's Bay Today the scam was "without doubt among the top five most active and longest scam campaigns we're tracking in our systems".
"It's been going on since 2008 in the US, but now expanded across multiple countries.
"They [the scammers] mostly use Microsoft brand names."
A Ministry of Consumer Affairs spokesman said computer virus scams were usually run from overseas call centres.
"You'll be called at home by somebody claiming to be from a technical support company ... The caller will tell you that your computer has a virus. They'll ask you to log on to your computer and to download a piece of software. This gives them remote access to your PC." They would then access personal details like email addresses and bank or credit card details. "If someone calls you out of the blue to say your computer has a virus, just hang up.
"Don't be intimidated by the callers, who can become very aggressive. Don't try to get any details from them. Just hang up." On Saturday Ms Hewetson took her phone off the hook and went away for the night.
The strategy seemed to have paid off as she received no calls yesterday.