Generation of designer file failed: Unknown server tag 'dx:PanelContent'.

Hello Krzysztof,

Thank you for the report. I've tried to reproduce your issue in a sample project, but failed. Please take a look at the screencast.
I assume that you get an exception, because you haven't registered the ASPxPanel namespace:

	
[ASPx]
<%@ Register Assembly="DevExpress.Web.v9.3, Version=9.3.2.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a"
    Namespace="DevExpress.Web.ASPxPanel" TagPrefix="dx" %>

If your issue isn't solved, please send me a small example which reproduces it.

Thanks,
Vest

Hello Vest,

I've seen your video but i think it's not the same. Please review my screencast.

I read breaking changes again. I've solved this issue by removing the panelcontrent variables from designer files. Second I removed added reference tag (dx) and changed PanelContent to another prefix dxp (which I have registered in my web.config). My project runs but still there is an issue which was recorded in my video.

Regards,
Krzysztof

Hello Krzysztof,

Yes, I've reproduced the issue with v2009 vol 3.2 version of DX controls. The ASPxRoundPanel (and other panel-kind controls like the ASPxCallbackPanel) doesn't register the ASPxPanel namespace when you first put the control into the "Source" view. Even if you switch to the designer and change the panel's content, the ASPxPanel isn't registered.
The temporary workaround is:
- you should put the ASPxPanel near the ASPxRoundPanel (to register the appropriate namespace). You can then safely remove it.
- or, you should put the ASPxRoundPanel (the first time) in "Design" view. The control registers two namespaces correctly.

Actually, this behavior should be thoroughly examined. I've forwarded this report to our developers for a detailed examination. Sorry for any delay.

Thanks,
Vest

Hello Krzysztof,

We are sorry for the delay.
We've examined this issue thoroughly, and found its inconsistent behavior. Actually the Visual Studio 2008 doesn't register additional namespace when the ASPxRoundPanel (and other panels) is used. The ASPxPanel isn't registered for all latest versions of DX controls: v2009 vol 1, v2009 vol 2 and v2009 vol 3. We think that this is an IDE specific issue. I'm sorry, but we couldn't even find any exceptions or unexpected behavior of namespace registering mechanism.
A possible solution was proposed in the previous report.

Thanks,
Vest

Hello Vest,

Thank you for the explanation.
If you found and also think that this is an VS2008 inconsistent behavior please report it to Microsoft.

Regards,
Krzysztof

Hello Krzysztof,

Unfortunately we can't add any report related to this issue to Microsoft. Actually MS VS2008 was released a long ago, and we aren't sure that the bug will be fixed in this version. You can also test a similar behavior in MSVS2010 which is still a beta and inform us if glitches appear.
Anyway, I've forwarded this report to our developer team, so that they can report it to Microsoft. This might take time, so, I can't say when an appropriate report will be created. I'll provide any further information when it becomes available.
Please bear with us.

Thanks,
Vest