Police probing the disappearance of an Inverclyde woman last seen in public in 1999 have said visitors to the house where she lived had not seen her.
A number of people told police they visited the house in Inverkip either to socialise or through their work, but had not seen Margaret Fleming.
The 36-year-old was reported missing by her two carers at 17:40 on 28 October.
However, apart from her carers, the last independent sighting of her was on 17 December 1999 at a family gathering.
The excavation of the garden of the house, Seacroft on Main Road, is to continue.
The house belongs to Ms Fleming's carers, 75-year-old Edward Cairney and 56-year-old Avril Jones, who were family friends.
Det Ch Insp Paul Livingstone, who is leading the inquiry, told BBC Scotland they had heard from a number of people who had visited Seacroft.
"Unfortunately that hasn't taken our inquiries any further forward with no other confirmed sightings of Margaret," he said.
"I'm really keen to speak to anyone who may have been at Seacroft over the past 20 years either socially or on business.
"It may well be they've been making a delivery - whether it's parcels or takeaway food."
Police are to distribute leaflets to local residents and businesses in Inverkip and Port Glasgow in the hope of jogging people's memories.
Ms Fleming, who is believed to have learning difficulties, is thought to have attended James Watt College in Greenock between 1996 and 1998.
Police Scotland had appealed for information from anyone who knew Ms Fleming during her college days.
Officers said she had few contactable friends or family and checks on education, employment, health and welfare records had shown no trace of her.
'Social work issue'
Her carers are helping police with their inquiries.
Det Ch Insp Paul Livingstone said: "They were her carers up until 28th October, and everything was normal as it should be.
"It is concerning that it's been six weeks since Margaret has gone when she did need help in her day to day life."
Police officers had gone to Ms Fleming's house on 28 October about a social work issue.
Her carers said she had left that day. They later reported her missing.
Police have also confirmed that Ms Fleming's carers assisted with her finances.
It is believed Ms Fleming lived with her father in Port Glasgow before he died in October 1995.
She then lived with her grandparents and mother but moved in with the carers in 1997.
She is thought to have been estranged from her mother since then.
Det Ch Insp Paul Livingstone said Ms Fleming's mother, who is originally from the Inverclyde area, was upset and concerned.
"She just wants Margaret back safe and well," he said.
"She does not want to make an appeal at this time."
Det Ch Insp Paul Livingstone also said Ms Fleming had enjoyed visiting Port Bannatyne and Wemyss Bay.
He said CCTV and door-to-door inquiries had failed to yield any sightings.