As long as the lock is physical
Open Seal is a little nifty trick that makes a "closed or locked physical device" operate itself to the open or unlocked state. It does not differentiate between a simple tumbler lock, a wafer lock or an electronic, solenoid-actuated deadbolt or strong magnets (aka Maglock): as long as the locking mechanism is somehow physical, the state flips and it opens.
The difficulty gets higher the more technologically advanced the area is, and electronic locks tend to be in either very weavery areas. An oil derrick in the boonies is at least "Rural Countryside" for Gauntlet 6, but more likely notches it to 7 right around it. A chemical plant would be at least Gauntlet 7 for an "Average City Street", but with the many pipes of high tech, it might be better comparable to "Inner City, Downtown". And a laboratory has Gauntlet 9.
Gauntlet isn't static over time!
The Gauntlet in a location can shift depending on activity and the presence of the pattern spiders that create the Gauntlet.
Think of it this way: It's 1990. The An-Nafud Desert has Gauntlet 5 on an average day, as we are in deep wilderness, just a few roaming pattern spiders keeping the Gauntlet existing.
Then some dictator comes along to threaten Kuwait. The August comes, the US calls Desert Shield and with it roll in soldiers, armed with bulldozers. Within less than a day the camp area is at Gauntlet 6 - Deep Wilderness turned Rural Countryside by the sheer amount of pattern spiders in the luggage of the troops. The tents get a sand wall, more tech arrives with pattern-spiders riding shotgun on trucks and dozers and within another day to week, the Gauntlet is up to 7, and using Open Seal to get to the documents in the HQ safe deposit box is getting harder.
As the weeks go on and boredom sets in, the gauntlet might rise as high as 8 in the central areas of the base - HQ and food court - while the area that can be considered "rural countryside" spreads as far as the patrols and training areas go.
The clock strikes 3 AM Bagdad Time on the 17th of January 1991 and Desert Storm starts, the pattern spiders ride in the wake of tanks and jeeps, leaving behind their work in the camp and slowly the pattern unravels. The day the camp is abandoned, the safe left behind in HQ sits only in Gauntlet 7, as human activity plunges towards nonexistence. Some days later, the former hub of the base is back to being at best "Rural Countryside" again, and maybe a month later the deserted lockbox is sitting in "Deep Wilderness" once more.
It doesn't work on "locked" computers
A computer that is "locked" is not in the scope of the gift - the item you want to unlock is not the computer, it is the operating system, which is not actually physical.
While you can't directly attack the computer, you still could open a door-lock which is operated by the computer: You need to use Open Seal on the physical lock, which is part of the door that keeps it shut.
