Nicola Sturgeon has today apologised for the confusion and difficulties users faced when trying to register for the vaccination record app over the weekend.
The First Minister also confirmed that the PDF vaccination records and letters available from the NHS will also be valid proof of vaccination status.
They will be required to enter venues deemed "high risk" by health experts - including nightclubs, music venues and large sporting events.
The Covid-19 certification scheme came into effect at 5am on Friday October 1 but will not be enforced until October 18.
The app had many teething problems and crashed multiple times due to a failure with the NHS systems the app was linked to and the high volume of users.
The First Minister said: “I am of course well aware that many people found it extremely difficult to use the app initially.
“In particular, many found that the app was unable to locate their vaccination record from the information that they provided.
“This problem was especially acute over Thursday evening and Friday.
“I know this caused extreme frustration for users who wanted to download the app as quickly as possible, and also for businesses and events organisers who were planning to test their certification arrangements over the weekend.
“I apologise for that.”
She continued: “The problem was not with the app itself but with the NHS systems that it links to.
“Essentially the high level of demand after the launch of the app – combined with an error in one part of the NHS system – meant that information wasn’t being sent quickly enough from the NHS system to the app.
“This also, for a period, caused problems for those requesting paper copies of vaccination certificates, or seeking to download a PDF."
Since its launch on Thursday afternoon Deputy First Minister John Swinney said more than 280,000 people had downloaded the app by the end of the weekend.
