The police watchdog has highlighted failings in the way police responded to concerns about a vulnerable man who was later found dead in his Edinburgh home.
The body of Andrew Bow, 36, was discovered on 23 March 2016.
The Police Investigations and Review Commissioner (Pirc) found officers were not sent to his home on four occasions when concerns were raised.
Police Scotland apologised to Mr Bow's family for "shortcomings" over the events surrounding his death.
Commissioner Kate Frame said it was not possible to say whether he would have been found alive if there had been an earlier response.
The investigation centred on Police Scotland's handling of telephone calls about Mr Bow's welfare in the week before his body was found.
The control room at Bilston Glen had previously been criticised in 2015 following the deaths of John Yuill and Lamara Bell, who lay undiscovered for days after a crash on the M9 near Stirling despite a sighting of their wrecked car being reported to the control room.
Mr Bow, who had Asperger's Syndrome, was last seen by police officers on 12 March last year when they found him in a confused and paranoid state.
The Pirc report said staff at the City of Edinburgh Council had sent a report to Police Scotland on 16 March asking for checks to be carried out following reports that the windows in his flat were broken. However, no action was taken.
Five days later, a local shopkeeper called 999 to report the broken windows and offered to help police find the house, due to the confusing house numbering system in the area.
However, area control room (ACR) staff at Bilston Glen did not send officers to the scene as they did not consider that any police resources were available at that time.
The shopkeeper contacted the control room again the following morning, and again staff decided that no police resources were available to be dispatched.
Later that same day another neighbour contacted the control room to raise concerns for Mr Bow's welfare.
Pirc said: "At this point, ACR staff were aware of the two previous un-actioned 999 calls and of concerns being expressed for the occupant to the effect that he may have 'hurt himself' or 'committed suicide'.
"Again, no officers were sent to Mr Bow's flat at that time."
On 23 March, a police sergeant in the Edinburgh area read details of the incident on the police system and decided to send officers to Mr Bow's flat.
They forced entry and found Mr Bow dead inside. The post-mortem examination was unable to provide an estimated time, date or cause of death.
In her findings, the commissioner said: "It is particularly concerning that despite several members of the public contacting the police to express their concerns, Police Scotland appear to have taken no action in relation to the first approach and thereafter in response to the subsequent calls, failed to dispatch officers who were available, timeously, to investigate.
"Whilst there may have been confusion in identifying the correct address from the original report, the person who contacted the police on the second occasion offered to remain at his premises and point out the flat to officers.
"Had that opportunity been taken, the police would have been able to identify the deceased's flat and investigate matters sooner."
She added: "Since it has not been possible to establish precisely when Andrew Bow died, it is not certain whether an earlier response by police could have led to him being found alive and his life saved.
"I have made a number of recommendations to the chief constable to ensure the handling of calls by staff at Bilston Glen are managed better, within the required timescales and that all available officers are sent to priority calls, especially those of concern about a vulnerable person."
Police Scotland Assistant Chief Constable Nelson Telfer said the force had made "significant changes and improvements" since the incident.
"Even after the passage of time, our thoughts remain with Andrew's family and friends," Mr Telfer said.
"We do, however, note the recommendations within the Pirc report and acknowledge the fact that there were some shortcomings in relation to the events that led to Andrew's death in March 2016. We would like to offer our sincere apologies to Andrew's family and friends for that.
"We must learn from these findings to further improve our call handling and management and deployment of local policing resources."