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Microsoft Office 365 to block Flash and Other Plug-ins


Two weeks ago, Microsoft announced that they would block future content that is embedded with Adobe Flash, shockwave, and their own Silverlight plugin from Office 365. But now Microsoft has gone a step further, announcing plans to deactivate Flash, Shockwave, and Silverlight entirely. This goes further than just a block of the plugins that can be turned off, this means that in only a few months, these applications will be gone from Office 365 for good.

What media will be affected once this is implemented?

Any Flash, Shockwave, or Silverlight content that uses Microsoft’s OLE (Object Linking and Embedding platform) and the “Insert Object” feature will be blocked. However, and media that uses the “Insert Online Video” control via the Internet Explorer browser will not be affected.

The following timeline shows the various changes that will take full effect by January 2019:

June 28: Controls in the Office 365 Monthly Channel will be blocked

September 2018: Controls in the Office 365 Semi-Annual Targeted (SAT) Channel will be blocked  

January 2019: Controls in the Office 365 Semi-Annual Channel will be blocked

Why did the developers choose to take out the embedded content?

Although this decision will likely be controversial with many people, Microsoft has various reasons for blocking these applications. They cited an issue in which Malware creators were exploiting systems through Word, Excel, and PowerPoint files with embedded content. On top of that, Microsoft pointed out that most Office 365 users rarely used these controls anyway.

This decision was influenced by more than just the issues Microsoft has had. The developers at the company decided to take action after Adobe announced that Flash would no longer be supported after 2020. Even Silverlight, Microsoft’s own product, was discontinued in 2016.

For the businesses that still need to embed Silverlight or any other Flash-based content in an Office 365 document, Microsoft has provided a support page on how users can re-activate the controls. Microsoft’s once-popular platform has experienced a steady decline over the years as websites have transitioned from Flash to HTML5. According to Google, chrome users that use Flash media has dropped from 80% in 2014 to below 8% in 2018.