The issue with the UK government Lighthouse lab in Glasgow has caused 64,000 tests to be re-routed to other sites. Tests from around the UK will be affected over the weekend.
Scotland has recorded a further 316 positive Covid-19 tests, the latest Scottish Government figures show.
However, the Government warned it did not reflect the total number of new cases or new tests, saying there had been a ‘processing delay as a result of a capacity issue’.
They said any additional cases will be reported in the coming days.
There were no new deaths reported relating to coronavirus.
The total number of fatalities still remains at 2,609, though separate figures from the National Records of Scotland, which records all deaths where coronavirus is mentioned on the death certificate, suggest the true death toll is 4,301.
There are now 703 people in hospital confirmed to have the virus as of Saturday, up by 28.
Of these patients, 62 were in intensive care - the same as the previous day.
Sunday's test results were delayed due to a capacity issue in the UK Government Lighthouse facility in Glasgow.
A statement from the Scottish Government said: "We were notified late last week of a testing capacity issue with the UK Government Lighthouse facility in Glasgow.
"This has meant around 64,000 tests from across the UK, including Scotland, will be rerouted this weekend (Friday-Sunday) to other testing sites in the UK and Northern Ireland, including tests from our physical testing sites, for example Regional Tests sites.
"It is important to note that the majority of these tests are still well within the 24 and 48-hour timeframe for results albeit we do expect to see an increase in the level of positives on Monday and Tuesday when the results are reported.
"The Scottish Government is urgently trying to establish with the UK Government what exactly is causing the delay in testing but this is mainly due to demand from out with Scotland.
"We continue to reroute routine testing of care home staff through NHS Scotland testing facilities to ensure prompt turnaround times."