The survey was complied over a six-week period by Chevin, a network software supplier. Researchers found that out of the 520 calls received by the UK helpdesk, the most common complaint was network card failure.
Network cards have generally been considered very reliable. However, Chevin found that 19% of helpdesk calls came from IT managers who encountered problems because they had installed less reliable network cards. A 10/100 Ethernet card from a leading manufacturer such as 3Com is often three times as expensive as an unbranded card, but 3Com would claim its product offered far higher levels of reliability.
The survey also found that 29% of helpdesk calls came from network managers with badly configured routers. Often installed months earlier, the routers would begin causing problems when faced with unusual network traffic.
Commenting on the survey, Chevin's vice-president of marketing, Koby Amedume said: "It was a bit of a surprise to see such simple faults and human error cropping up as major headaches."
Network managers were under a lot of pressure and were often expected to learn from mistakes instead of getting proper training, he added.