Microsoft fixes issue with Windows Phone Marketplace digital certificates
WMExperts

Microsoft has finally issued a fix for the Marketplace problem that prevented Windows Phone users from installing new apps or updating existing ones for the last few days. According to a post on the Windows Phone Developer Blog, the fix for the digital certificate bug is currently being rolled out and make take up to two full days to deploy and completely get rid of the problem. Windows Phone users should now be able to install or update apps with ease.

What Else You Need To Know:

- Some of the most notable apps that got affected are WhatsApp, Translator from Bing, and the New York Times app.

Other sources

WMExperts
Microsoft fixes Marketplace certificate issue for Windows Phone. App submissions are a go.
WM Power User
Marketplace app update bug stomped, says Microsoft
Engadget
Microsoft resumes publishing Windows Phone apps, all is right with the world
Geeky Gadgets
Microsoft Windows Phone Apps Publishing Resumed  

Now it would appear that Microsoft has fixed the issue, and has resumed publishing of new Windows Phone apps to its mobile apps store, as it has now fixed the issue with the digital certificates.

Phone Arena
Microsoft fixes Marketplace issue, resumes new app publishing
Other
Microsoft resumes publishing Windows Phone apps
The Inquirer
Microsoft starts publishing Windows Phone apps again
Daily Mobile
Microsoft fixes app signing problem, Marketplace is back to normal  

This is also good news for developers and they can start submitting their apps again.

InfoWorld
Microsoft resumes publishing Windows Phone apps
Mobile Burn
Microsoft resumes Windows Phone app publishing
 
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