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Re: Microsoft Silverlight

Hi All

By adding text/xml  to the whitelist along with 3dr and .xap then I now have a larger proportion of Silverlight content displaying but obviously it is not ideal that I would have to whitelist these media types for all our users. I installed the firefox add on as suggested which is a useful little tool (I already had the IE equivalent).

I still cannot get the content on this page to display through the proxy and I get a server error. I think (from looking at the headers in firefox) that it is the zip file that is the problem that it needs to download to launch

Michael is there no way of creating a media type of Silverlight in the same way there is one for flash?


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Message 12 of 22

Re: Microsoft Silverlight

If you wish to add a media type for Silverlight you can do the following:

It may be necessary to add a media type catalog entry under Common > Media Type Catalog, see below for the information to add:

Add or modify Media Type: application/x-silverlight-app

File Extensions: xap

Magic bytes are necessary: checked

Magic bytes are ambiguous: unchecked

Offset: 0

Magic bytes: 504B0304

I worked with agperzan, and we also added a whitelist entry for the media type:

Type: String

String: application/x-silverlight-app

Entry type: Media Type

Apples: Any type

That worked!



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Message 13 of 22

Re: Microsoft Silverlight

Jon, signature that you specified will also match to standard .zip archives (Siliverlight applications are really code packed into .zip archive).

In MWG7 we have special checker for zip-based files, that allows us to distinguish sliverlight from other types.

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Message 14 of 22

Re: Microsoft Silverlight

Thanks Jon it works on MWG 7.1.0 

Re: Microsoft Silverlight

Jon, Can you add a screenshot for 7.3.2 where you add the catalog entry under Common > Media Type Catalog

I can't seem to find that.

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Message 16 of 22

Re: Microsoft Silverlight


That doesn't exist in Web Gateway 7. For mwg 7 you typically just need to whitelist from progress pages.

Re: Microsoft Silverlight

It looks like I have the same problem but with the added difficulty of sliverlight not supporting proxy authentication. When in our organisation an older client (xp/win2003) opens the content, it switches to windows media player with a login prompt. But when a new Win 7 client opens the content it only wants to use Silverlight.

Re: Microsoft Silverlight

hello all,

i am struggling with the same issue. we are running mcafee webgateway 6.9 and users are having issues with playing silverlight videos.

has anyone found a definitive fix for this issue?

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Message 19 of 22

Re: Microsoft Silverlight

Dear all

I run into the same issue regarding the media type "application/x-silverlight-app" which seems not to be available also in MWG If I read through this thread I'm not fully clear about if I can define custom media types unter MWG7? The one says "works on mwg7.1, the other says that does not exists in mwg7". Whitelisting separate url is not such a fancy solution, so am I able to define a custom media type in MWG7 or not?

Thx, Stefan

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Message 20 of 22

Re: Microsoft Silverlight

Hi Stefan

In the catalog we have the type 'application/x-silverlight' - I think, that the name was changed to match the "official" mime type from Microsoft

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