OUTLOOK users have been left in shock after a font is quietly changed for the first time in 17 years - but users can switch it back.
The familiar font has been a staple for the past two decades but it is now being replaced.
The software giant has suddenly swapped the beloved Calibri for a new default font named Aptos.
But the move has left users less than thrilled.
The unexpected switch has left many scratching their heads and slamming the decision on social media.
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One user took to TikTok to share the shock, said: "Out of nowhere my work computer changed the default font from Calibri to whatever this is and it feels like kind of sick joke."
Many have grown used to the comfort of the font's rounded stems and corners since it was launched in 2007.
However, Microsoft announced it was bidding farewell to Calibri in 2021 - marking an end of an era.
Aptos, which has influences from mid-20th-century Swiss typography, is now taking over.
The sans serif font is similar to Calibri but with distinct features.
It boasts bold, well-defied, directive and constrained looking- with clean-cut stem ends.
Letters are also have subtle circular squares within the edges for a better readability.
However, despite the enhanced features, tech enthusiasts are not satisfied with Aptos.
Posting on TikTok, one user said: "The fact that's its only a tiny bit different is what's driving me absolutely insane."
Another added: "This happened on my Outlook and it's caused a professional identity crisis."
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And a third blasted: "Wait mine did that today too I thought I was going crazy."
Luckily for loyal Calibri users, the change is not permanent as it can be switched back.
Microsoft has provided a straightforward method to revert to the classic font.
All you need to do is open Microsoft Word navigate to Home, and select the Font Dialog Box Launcher.
From here, choose Calibri and your preferred size.
Then opt for 'Set As Default' and you can add it to the current document.
Once satisfied with your selection, press OK.
It comes as thousands of people reported issues with Microsoft Teams.
Reports are down to 200, from over 14,000, as of 7:30pm EST, and customers are reporting resolutions.
Meanwhile, a genius WhatsApp hack taught thousands of users how tweak a major feature.
A TikToker has revealed how to quickly change the font used in the app with series of easy tweaks.