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I did find a decent 4th option on machines I have control over. That is to create a shortcut to IE, and path to the site (see below). Still would like to modify the logon page to notify users of the issue.<br />
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<b>&quot;%ProgramFiles(x86)%\Inter<wbr />net Explorer\iexplore.exe&quot; <a href="https://myowasite.com/" rel="ugc">https://myowasite.com/</a></b>
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This didn't sound right to me, and I am unable to replicate your results. I just fired up Edge, connected to an Exchange 2010 SP3 OWA mailbox, and opened word document attachments, a PDF, and others. No issues here...
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Not open attachments, open the window to attach a file.
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I can't get the attach file screen to pop up at all, even with pop up blocker turned off.
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Consider using IE 11 on Windows 10. I do this and I made IE 11 default. It works and Edge is new and still has issues.
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John, thanks but I'm more concerned with how to let my remote users know this. Regardless of the workaround I need a way to let windows 10 users know that there is an issue, and to take that option. Otherwise they end up calling me assuming our side is broken. I would actually prefer that, as then I could fix it.
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So Cliff, can you confirm this is no longer an issue in 2016/365?
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<div class="content wysiwyg-content">
Well after searching a bunch, it looks like OWA on Exchange 2010 is broken on windows 10's edge browser. It opens fine, but won't open the attachment window. Fine job there MS!<br />
<br />
There are 3 workarounds, use a different browser, open in IE via edge, or run the light version. We all know how users are, and all options kind of suck in their own way. I think I've settled on the &quot;best&quot; crappy way is to use the Open in IE option, but now how to convey that to Joe user logging in from his shiny new PC at home for the first time.<br />
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Ideally what I want to do is just Add a big red text line to our logon page. Something that says.<br />
<b><i><br />
Windows 10 users, Microsoft Edge does not support OWA. Please open in IE by clicking the 3 dots in the top right, and choose Open in Internet Explorer.</i></b><br />
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How would I go about doing that. I've read a bit about the OWA themes, but nothing I've seen addresses adding a paragraph to the logon.aspx page.
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Well after searching a bunch, it looks like OWA on Exchange 2010 is broken on windows 10's edge browser. It opens fine, but won't open the attachment window. Fine job there MS!

There are 3 workarounds, use a different browser, open in IE via edge, or run the light version. We all know how users are, and all options kind of suck in their own way. I think I've settled on the "best" crappy way is to use the Open in IE option, but now how to convey that to Joe user logging in from his shiny new PC at home for the first time.

Ideally what I want to do is just Add a big red text line to our logon page. Something that says.

Windows 10 users, Microsoft Edge does not support OWA. Please open in IE by clicking the 3 dots in the top right, and choose Open in Internet Explorer.

How would I go about doing that. I've read a bit about the OWA themes, but nothing I've seen addresses adding a paragraph to the logon.aspx page.

OWA and Microsoft Edge

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.

Exchange

Windows 10 is a personal computer operating system featuring the "universal application architecture" (UAP); apps can be designed to run across multiple devices with nearly identical code, including PCs, tablets, smartphones, embedded systems, Xbox One, Surface Hub and HoloLens. Windows 10 also includes a virtual desktop system, a window and desktop management feature called Task View, the Microsoft Edge web browser, support for fingerprint and face recognition login, voice-based search (Cortana), new security features for enterprise environments, and DirectX 12 and WDDM 2.0 to improve the operating system's graphics capabilities for games.