Microsoft stops devs from publishing new apps to WP Marketplace due to bug
The Inquirer

Microsoft has decided to temporarily prevent Windows Phone developers from pushing new apps to the Windows Phone Marketplace because of a problem with digital certificates that are causing users trouble with downloading apps. To be more specific, users who updated from earlier versions of Windows Phone to Windows Phone 7.5 have been unable to either install or update apps for the last couple of days. According to Microsoft, only a small percentage of all apps are affected, and users will be able to download updates and install apps once again as soon as a fix becomes available,

What Else You Need To Know:

- The Windows Phone Marketplace currently holds over 100,000 apps for users to download and install.

- Some of the affected Windows Phone apps include WhatsApp, Translator from Bing, and the New York Times app.

Other sources

Other
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Microsoft Suspends App Publishing To Marketplace After Error  

An error preventing Windows Phone users from installing or updating certain apps has led Microsoft to temporarily suspend the publishing of new apps to the Marketplace until the issue is resolved.

ReadWrite
Bug Forces Microsoft to Suspend Publishing Apps to Windows Phone Marketplace  

If you tried to download or update an application from the Windows Phone Marketplace this week, there is a good chance that you received an error message.