Astronaut John "Danny" Olivas used his hands, staples from a medical kit and pins to repair a thermal blanket on the back end of space shuttle Atlantis that came loose during liftoff a week ago.

Olivas completed his work as Jim Reilly changed a vent on the outside of the international space station and NASA worked with the Russian space agency to fix crashed computers at the space station.

With the astronauts still outside and preparing to help retract old solar arrays, Russian controllers attempted to reboot the computers, which control essential functions on the space station such as how the station is positioned and the oxygen system.

The computers are actually two sets of three computers. NASA-TV reported Friday afternoon that each set of computers was working in two of the three channels.

Cosmonauts Fyodor Yurchikhin and Oleg Kotov bypassed a power switch with a cable to get two out of three computer connections running, said Lynette Madison, a NASA spokeswoman in Houston.

At a news conference earlier Friday afternoon, NASA discussed the computer problems and stressed that there was no immediate danger, officials said.

Space station program manager Mike Suffredini expressed confidence at the midday Friday news conference.

"There is nobody in this agency ... that thinks this vehicle is at risk of being lost," he said.

He said that even if the crew had to leave, more people could be sent up later.

Suffredini said that carbon dioxide scrubbers are still working on the station and that there is plenty of oxygen for the crew. Earlier, a Russian official said there was air for 90 days.

Plus, the U.S. will test another oxygen generator -- as previously planned -- that could take up the slack from the Russian equipment that is down because of the computer problems.

He said that the backup power supply on two of the six control computers may have failed permanently, though the data was not yet clear.

Problems with the computers began to develop when a connection was made with the newly installed solar panels on the station. Suffredini said that the connection in question is just for a future part of the station, so it may be disconnected.

However, when power from the new array was tested, it did not appear to have any problems that could damage the computers, which was an early theory.

Attitude Control

Besides the life-support functions, the damaged computers control the position of the station, which helps it maintain power and its height in orbit. Gyroscopes that are still working can take some of that work, but may have difficulty with major changes, such as when the shuttle leaves.

It was not clear how attitude control -- which refers to the direction the craft is pointing -- would be regained. Suffredini said a team was studying that problem.

The computers in the Russian service module failed overnight Wednesday, U.S. time. They were briefly believed to have been repaired on Thursday, but later failed again. Cosmonauts worked through the night until flight controllers told them to get some sleep after changing where the power was coming from did not solve the problem.

If the computers can not be repaired, it could make the orbiting outpost inoperable.

Russian officials have offered to move up the launch of a unmanned supply mission to sometime in July from August.

A NASA official said the chances of abandoning the station were remote. A Progress or Soyuz capsule, an unmanned vehicle that brings supplies to the station, is always kept there as an emergency escape capsule.