Students returned to classes at Arapahoe High School on Tuesday.
The Douglas County School District emergency message system failed during the shooting at Arapahoe High School on Friday.
The district sent this statement to 7NEWS explaining the problem:
Upon our initial reviews, it seems as if our District-parent communications portal -- Infinite Campus -- was unable to handle the quantity of emergency messaging that we sent to our families. The IC system didn't work properly and we're already in the process of ensuring that any issues are resolved.
District spokesperson Michelle Yi confirmed to 7NEWS they tried to send an email and text message to 73,000 contacts Friday at 1:45 p.m. Parents on Facebook report getting the message as late as 7 p.m. Yi explained when they tried to send the message the screen froze.
"We have the security team, which is assembled with people as high as the chief operating officer, the district, to security people, to the IT department, just dedicating their time and resources to making sure this doesn't happen again," she said.
While Arapahoe High School is in the Littleton Public Schools district, surrounding districts like Douglas County imposed precautionary security measures at their schools and initiated protocols to alert parents about what was happening.
Parents were clearly upset by the Douglas County district's overwhelmed alert system.
One mom posted on the 7NEWS Facebook page, "What if this tragedy had happened at a DCSD school? Our system failed the test."
7NEWS contacted the vendor Infinite Campus, which the district identified in its statement. Infinite Campus spokesperson Eric Creighton said they were unaware of the problem until 11a.m. Tuesday after 7NEWS first contacted them. Creighton said upon initial review it appeared the district did not use "best practices" to send the message.
Creighton explained the district had multiple people trying to send the message at the same time, which overwhelmed the system. He also said there was a glitch in the alert system software, and the company had sent the district an update to correct it in October; however, DCSD had not updated the software yet.
In an interview Tuesday, Yi told 7NEWS, "We found it just as frustrating to not be able to send this correspondence out...At the end of the day, the job is to be done by us and clearly it didn't go through and we're going to figure out what happened so it never happens again."
Infinite Campus told 7NEWS these are preliminary reports and they have contacted the district to get a better idea of what went wrong.
Various Douglas County schools sent letters to parents explaining the problem.
SkyView Academy was one of the schools who contacted parents. They assured parents that administrators and staff will spend time revisiting security protocols, officials stated.
"There will be additional police support for every DCSD School Resource Officer beginning Monday," officials said.
"Parents and staff are encouraged to be careful not to let any anxiety they are feeling be felt by students," officials suggested.
"Our staff is well prepared to respond to students who approach them about this incident in developmentally appropriate ways," officials said. "Staff responses will vary depending on the age of the student and each principal will work with their teachers to determine the best message for students in primary, elementary, middle and high school."
"As educators our hearts are broken for the staff and students who are dealing which such a tragic situation," the statement continued.
Coverage: Arapahoe High School Shooting
Teachers and staff went back to work at Arapahoe High School on Monday. Students will return to classes on Tuesday.
An online petition drive is asking Littleton Public Schools to give Arapahoe High School shooting victim Claire Davis a diploma at graduation in May.
When an armed student went into Arapahoe High School on December 13, many people sprung into action.
Claire Davis' father asked people to forgive the fellow student who shot and killed his 17-year-old daughter at Arapahoe High School.
The Arapahoe High School shooter entered the school through a door that should have been closed and locked, but was left ajar, Arapahoe County Sheriff Grayson Robinson said.
Gov. John Hickenlooper orders flags lowered to half-staff Wednesday in honor of Claire Davis, the student slain in the Arapahoe High School shooting.
Tickets to the celebration of Claire Davis' life are now available for students and staff at Arapahoe High School.
Claire Davis will be celebrated next week with a memorial at the National Western Stock Show and Complex.
Prosecutors are warning people that scam artists may try to take advantage of the shooting death of Claire Davis at Arapahoe High School by setting up phony websites and requesting donations.