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This cumulative update fixes several issues. The update contains an image that can be installed on Aastra 6721ip and Aastra 6725ip telephones. The image version is 7577.4531

Get Cumulative Update KB4019527 for Lync Phone Edition for Aastra 6721ip and Aastra 6725ip

The cumulative update is available for download from the Microsoft Download Center:

DownloadDownload the UCUpdates.exe package now.

 Release Date: April 2017

For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to obtain Microsoft support files from online servicesMicrosoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.

How to install the update


There are no prerequisites for installing this cumulative update.

Restart requirement

You may have to restart the computer after you apply this cumulative update.

Update replacement information

This cumulative update replaces theSeptember 2016 cumulative update for Lync Phone Edition for Aastra 6721ip and Aastra 6725ip telephones.

Registry information

To use one of the cumulative updates in this package, you don't have to make any changes to the registry.

Issues that the update fixes

This cumulative update fixes the following issues:

This cumulative update also fixes the Lync Phone Edition for Aastra 6721ip and Aastra 6725ip issues that are described in the following Microsoft Knowledge Base (KB) articles:


See the general information about the standard terminology that Microsoft uses to describe software updates.

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