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Owners of Lumia 520, 521. 525 and 526 smartphones who have wanted to get the Windows 10 for phone preview build should be able to download it again on Tuesday, April 21. Microsoft has now solved a problem with those devices when rolling back from the preview build back to Windows Phone 8.1.

Read more: Windows 10 for phones preview could go live again for Lumia 520 devices on April 21 | Windows Central