Scotland's largest health board has said its IT system is working again after a two-day crash saw hundreds of appointments and procedures cancelled.
NHS Greater Glasgow and Clyde said it still does not know what caused the problem which affected 11 hospitals.
The health board said no patient information had been lost and data gathered during the crash would be manually added to update the system.
All patients with appointments on Thursday should attend as normal.
The computer system crash meant that 599 outpatient appointments were postponed along with 62 planned inpatient procedures and day cases and 48 chemotherapy patient treatments.
NHS Greater Glasgow and Clyde (GGC) chief executive Robert Calderwood reiterated his "unreserved apology" to patients and said those affected would be given new appointments.
"Although 709 patient episodes have had to be postponed our staff were able to see some 10,000 patients using manual back up systems," he said.
"I can also report today that some of the patients affected have already been re-appointed and will be seen in the next few days.
"Arrangements are now being made to ensure that all the other patients affected will be offered a re-appointment as quickly as is possible."
Mr Calderwood said the "unprecedented" systems crash related to the health board's computer network and the way staff connected to clinical and administrative systems.
"The situation is that as users log on they go through a system called Microsoft Active Directory, a router system which recognises users and allows individual access to our clinical and administrative support systems," he explained.
"This was corrupted over the weekend which became apparent when staff logged on to the system on Tuesday after the holiday weekend."
Although the problem has been resolved, NHS GGC still does not know what caused it.
A statement from the health board said: "The platform on which NHS GGC's IT systems are built are in common with most large organisations in the UK and indeed the world.
"At this stage it remains unknown what exactly caused this problem to occur and this is one of the major issues and we continue to work closely with Microsoft to get to the root of the problem."
The statement said: "Our IT teams and our external experts are continuing to run full diagnostic checks to try and understand exactly what caused the problem in the first place."
"NHS GGC IT teams working in collaboration with international experts from our suppliers at Microsoft and Charteris will continue to closely monitor the situation as clinical staff begin their work today."
BBC Scotland understands that the IT systems crash affected patients with appointments at 11 hospitals. These were:
- New Victoria Hospital
- Victoria Infirmary
- Vale of Leven
- Royal Alexandra Hospital
- Inverclyde Royal Hospital
- Glasgow Royal Infirmary
- Southern General Hospital
- Western Infirmary
- The Royal Hospital for Sick Children
Maternity and emergency services were maintained throughout the crash.