Report a Silverlight Bug

Re: Re: Re: Re: HTTP 400 error connecting to Foundry switch UI

AllThatJazz — Tue, 05 Aug 2008 18:26:50 GMT

WOW, good sleuthing!

I just tried this and it works as advertised. (once I realized that I had to include the "Accept: " in the 298 word maximum) I deleted two of the entries, for x-ms-application and vnd.ms-xpsdocument and was able to get to the web UI without any problem.

I'm going to forward this to Foundry so they know what's going on, too

Thanks again!

Re: Re: Re: HTTP 400 error connecting to Foundry switch UI

coryb891 — Tue, 05 Aug 2008 17:37:58 GMT

Expanding on the previous post (MPB and I both worked on this issue)...

Our device is a DLink DCS-2100. The problem is apparently due to a buffer overflow isssue on the camera. The problem is with the "Accepts" header line in the request. In my browser, the header looks like the following:

Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-ms-application, application/vnd.ms-xpsdocument, application/xaml+xml, application/x-ms-xbap, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-shockwave-flash, application/x-silverlight, */*

I connected to the camera using telnet and pasted the request and received the 400 error. But if I reduce the length of the Accepts header by 8 characters (or say remove the application/x-silverlight entry) and paste this into telnet, I receive a normal response. The device cannot handle header lines longer than 298 characters (or 300 including the CRLF).

The workaround is to simply remove one of these entries. This can be done by removing one of the registry values located at the key that MBP posted. If you are using 32-bit IE on 64-bit windows, you will need to delete a value from

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Internet Settings\Accepted Documents

Hope this helps to solve your problem as well.

Re: Re: Re: HTTP 400 error connecting to Foundry switch UI

MBP — Tue, 05 Aug 2008 17:12:02 GMT

Same problem here but discovered that a registry entry length was the cause.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Accepted Documents

Make sure the above entries do not combine to exceed 299 chars. (at least for my DLINK device)

When it was at 300 chars or more got error 400.

When I changed it to 299 or less chars DLINK web interface worked fine.

I guess most people are installing Silverlight and this is one of the few apps that actually modify this registry entry.

Re: Re: HTTP 400 error connecting to Foundry switch UI

Yi-Lun Luo - MSFT — Wed, 18 Jun 2008 03:14:53 GMT

Hi, we're investigating this issue...

Re: HTTP 400 error connecting to Foundry switch UI

tcordes — Tue, 17 Jun 2008 17:18:11 GMT

I don't see anyone from MS replying on the topic, and no MSKB entry yet from what I can find. Start making a stink on the other thread. Isn't this forum supposed to have MS people watching it?

It's easy to see it's a Silverlight problem. Install SL, page breaks. Uninstall SL, page works. Use FF, page works. Can't argue with that logic!

Re: HTTP 400 error connecting to Foundry switch UI

AllThatJazz — Tue, 17 Jun 2008 13:08:57 GMT

Yup. That seems to be a similar issue. I'll post over there from now on. Do you know if MSFT has even acknowledeged this as a problem? Last official word I got was that it was "unlikely to be a Silverlight problem", then silence.

Re: HTTP 400 error connecting to Foundry switch UI

tcordes — Sat, 14 Jun 2008 18:34:55 GMT

See http://silverlight.net/forums/t/7452.aspx same problem?

Re: HTTP 400 error connecting to Foundry switch UI

AllThatJazz — Wed, 30 Apr 2008 17:47:37 GMT

I tried disabling the plugin, but the problem persists. Uninstalling Silverlight is the only thing that allows me to log in to the switch using the web UI via IE7.

As I stated in the original post, the problem is in connecting to the web based user interface of the switch, so saying "it has nothing to do with switches" just shows me that you aren't reading the full post. The browser most certanly does have something to do with accessing a web based UI! I have found some posts relating to similar problems with HP switches and d-Link devices, so maybe there is a wider problem here.

BTW, I've re-run all my tests with Firefox as the browser and Silverlight installed, and have had no problems connecting to the switches. Maybe it's an IE7 thing?

Re: HTTP 400 error connecting to Foundry switch UI

Yi-Lun Luo - MSFT — Mon, 28 Apr 2008 08:36:10 GMT

Hello, this is unlikely to be a Silverlight problem. Silverlight is a browser plug-in. It has nothing to do with switches. Try to disable the Silverlight plug-in without uninstalling and see if the problem gets away. If the problem persists, feel free to let us know.

HTTP 400 error connecting to Foundry switch UI

AllThatJazz — Thu, 24 Apr 2008 13:44:21 GMT

With Silverlight (1.0, 1.1 or 2.0 beta) installed, I get an HTTP 400 error connecting to the web UI of my Foundry switches. With Silverlight uninstalled, I can connect normally. I've seen a few posts with similar problems, but none concerning Foundry switches so I thought I'd include this to let you know that this seems to be a more widespread problem. Sorry, but I can't/won't deploy Silverlight until this issue is fixed.