Deployment of Digital Signature ActiveX control from within SharePoint fails

I've recently been investigating a rather curious problem we've been experiencing with deployment of the Digital Signature ActiveX Control from SharePoint 2007 to browsers.

First a little background: A number of workflows we've developed recently make use of the capability of InfoPath forms to incorporate sections that can be digitally signed. In general these forms are developed in InfoPath 2007, and are served from a MOSS 2007 farm into a browser window for the user. The forms are developed on a PC which has UK-English language and locale settings and are served from installations of MOSS 2007 which are typically configured for UK-English as well.

The first time a user sees a form with the capability to be digitally signed displayed in their browser window, assuming the Digital Signature Control is not already installed on their computer, they are asked whether they would like to install it:

Clicking yes, opens another window which presents them with a license agreement to read through and agree to. Checking the 'I agree...' checkbox and clicking the 'Next' button:

... results in nothing further happening. All rather curious.

After the usual investigation for such things (check the event log; nothing, check the MOSS logs; again nothing, turn on trace logging; again nothing), followed by discussion with the SharePoint support team and some Fiddler traces, we worked out that the Digital Signature Control installer (DSigRes.cab) could not be found on the SharePoint farm at the expected location of _layouts/2057/DSigRes.cab (2057 being the LCID for EN-UK). Indeed, when we looked for C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\TEMPLATE\LAYOUTS\2057 the folder didn't exist!

We tried installing the MOSS 2007 language pack, which made no difference.

As a workaround, I created the 2057 folder under _layouts and copied the DSigRes.cab file from the 1033 (LCID for EN-US) folder into it. This appeared to cure the problem and the Control installed succesfully.

At this point, the issue was escalated to the US InfoPath team. This morning the InfoPath team came back with their confirmation that this is indeed a bug with InfoPath and that it is not limited to UK-English, but at this time they do not have a complete list of the languages that it does affect.

They also confirmed that the workaround listed above is a reasonable solution at the moment.

When I hear that a Microsoft solution to this issue has been provided, I'll let you know!

Technorati Tags: SharePoint,InfoPath,Digital Signatures