AHMEDABAD: The trouble with the computer-aided CAT exam was diagnosed as ‘Conflicer’ and ‘W32 Nimda’, the two viruses that attacked the system display of the test, causing it to slow it down.Efforts are now on to quarantine the systems from these viruses to ensure smooth conduct in the remaining days. Tests at 47 labs were called off on the first two days and 33 labs on Monday, on account of this problem affecting nearly 8,000 aspirants who will be rescheduled.Samir Barua, director of IIM-A, which is the nodal agency for conducting CAT in the country, told reporters, "Though there were precautions taken, with so much of technology involved, it is hard to keep the system foolproof. The 47 centres which reported problems on Day one, were kept shut on Day 2 so that they could be checked. On Day 3, 33 were shut, which include some new centres also," said Barua."All efforts are right now diverted to further isolate and quarantine the individual servers, increase virus protection and control accessibility so that the test can be conducted smoothly on the remaining days. These security measures are being taken not only in the centres that have experienced problems but all the others that were operating smoothly," added Barua.Charles Karnan, COO, Prometric, the US agency given the contract for CAT 2009 along with NIIT, said, "All the students who have suffered any difficulty in the taking the test will be accommodated, as all the centres were asked to keep a buffer in case of any such problem, right in the beginning. Of the 8,000 odd candidates that have faced problem, 62% have been rescheduled." "This is the biggest test we have conducted. Usually these many students take tests like GRE, GMAT or Toefl across the year, but here we had to complete the process in 10 days," he said.Students facing problems at individual levels, have been asked to report to the Candidates Care Service at each centre. “Once their credentials are confirmed, they will be given a new test date and slot when they can appear for the test," Satish Deodhar, convenor of CAT Centre said.Asked how the three centres at Ahmedabad were glitch-free, Prof Deodhar, said, "The centres here were able to keep their servers quarantined better."