DOZENS of operations were cancelled at Raigmore Hospital as a result of damage caused by a leaking roof.
Torrential rain at the weekend forced water to build up on a flat roof which ended up flowing down into the basement where the computer servers are stored.
At least 26 operations had to be postponed but emergency operations were not affected.
NHS Highland insisted that no patients were put at risk.
A giant water pump was brought in to syphon water from the flat roof at the main entrance to the hospital.
IT experts were on site all night on Sunday supported by duty management who put in place "paper-based contingency plans."
A press release issued on Monday by NHS Highland said the servers supported hospital systems which were "unlikely to be fully functional for day-to-day business to commence".
Some systems were operating again by early Monday afternoon while staff resorted to pen and paper as part of their routine duties.
A spokeswoman for NHS Highland said: "There has been some detrimental impact to outpatient and theatre services.
"While all clinics have been running as normal, clinicians have been assessing these on a case-by-case basis and, unfortunately, some patients from clinics had to be cancelled."
She advised that unless patients had been contacted by the hospital, they should turn up for clinic appointments as normal.
She added: "Work continues on the recovery and connectivity of the servers to ensure that services will resume as quickly as possible."
The server damage affected the relay of reports and results from the hospital’s X-ray department and Raigmore’s laboratories, but bosses said work was continuing to ensure the resumption of normal services "as quickly as possible".
NHS Highland urged patients not to phone the hospital because its telecommunications systems were also affected.
In terms of the potential long-term impact on waiting lists, the spokeswoman said: "We will try and get patients booked in as soon as we can."
Monitoring the situation, Conservative MSP Edward Mountain said: "This incident proves the importance of good IT.
"I’d like to commend the hard work of those who are working to resolve the issues.
"It’s hoped this will be swiftly resolved and that the NHS has sufficient resilience in its system to ensure that no data is lost."
Highlands and Islands Labour MSP David Stewart said: "The weather was quite severe at the weekend and increasing rainfall and changes to rainfall patterns mean, unfortunately, we will be hit by more flooding in the future, causing more damage to property and disruption to services.
"I’m sure frontline staff will be doing all that they can to mitigate the effect on patients.
"I totally sympathise with those affected and sincerely hope that people going for surgery or outpatients appointments will find minimum disruption."
Local SNP MP Drew Hendry said: "While no-one would want to see any disruption to scheduled appointments, it’s right that those affected are contacted as a matter of priority."