The D.C. government’s online portal for registering for coronavirus vaccinations got bogged down again Saturday morning within minutes of offering thousands of slots to residents eager to turn the page on the coronavirus pandemic.

The surge to sign up arrived online at 9 a.m., when the city opened 3,500 appointments for people ages 18 to 64 with a qualifying medical condition in certain Zip codes, mostly in Wards 5, 7 and 8.

Then came the heartache and frustration of computer glitches that appeared to foil many residents.

“Thanks for your continued patience,” Mayor Muriel E. Bowser (D) tweeted at 9:33. “Microsoft had to restart their servers. Please try to book your appointment again.”

The city’s portal has had a bumpy rollout, like many vaccination initiatives elsewhere, as demand has outstripped supply.

Somehow, though, the Saturday slots were booked.

At 9:47, the D.C. health department tweeted: “Appointments that opened today are filled. More available for eligible residents in priority zip codes on March 4.”

Officials said more vaccination appointments will open up on Friday for residents 65 and older, for those 18 and older with qualifying medical conditions and others from eligible workforce groups.

That all appeared to be small consolation for people angry about the snarled and overloaded process.

“Please have a different system in place by then,” one Twitter user wrote at 9:56. “It’s one thing not to get an appointment because you weren’t first in line/didn’t follow the process, it’s another to spend 50 minutes, have literally ‘submitted’ your appointment booking, and still end up empty handed.”

But that same user delivered to the Twitterverse a happy postscript 25 minutes later: “FYI even after the appointments were all gone online at 9:55, I was finally able to get through on the phone lines and received an appointment. The young woman who helped me was so kind and patient, made this awful experience just a little bit better. Good luck all!”