The ban was issued to prohibit Slack's use in Iran, in compliance with the US trade embargoes and economic sanctions regulations.
But, it impacted those living as far as Finland, Canada, many with few remaining ties to the country.
Here's more on the issue.
Over the last two days, several Slack users (Iran expats, visitors) have taken to Twitter to report Slack's sweeping account ban.
The company served these users a single notice and banned their accounts immediately, without even giving time for backing up data.
Naturally, this led to a major uproar, with many claiming that the company was collecting information on its users' ethnicity or nationality.
So @SlackHQ decided to send me this email. No way to appeal this decision. No way to prove that I'm not living in Iran and not working with Iranians on slack. Nope. Just hello we're banning your account. pic.twitter.com/giqYQcMJYz— Amir Omidi (@aaomidi) December 20, 2018
A Slack representative later told The Verge that the accounts were deactivated due to an update of its geolocation system.
"We updated our system for applying geolocation information, which relies on IP addresses, and that led to the deactivations for accounts tied to embargoed countries. We only utilize IP addresses to take these actions. We do not possess information about nationality or the ethnicity."
Now, Slack has issued an apology and noted that most incorrectly deactivated accounts have either been restored or are in the process of being restored.
The company also said it will tweak its sanction compliance technique that disable access for IP addresses from Iran and other embargoed countries.
This way, access from the country in question would be blocked, but the account will remain.
"We acknowledge that we made several mistakes here," the company said in its public apology. "Our attempts to comply with these regulations were not well-implemented. In our communications, we did not treat our customers and other users with the respect they deserve."
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