Hi Shayne,

This sounds like a permissions issue.  The ASP.NET_WP isn't going to have acecss to root folders like C:\infragistics\gaugeimages, you would need to specifically grant permissions to that folder for that process.  Alternatively, you could use the virtual directory, which would have access granted through IIS.  However, anything under wwwroot gets 'stepped' on by SharePoint.  To tell SharePoint to keep its hands off your folder, you need to add it as a folder inclusion.  I think that might be the step you're missing.

Deploying

You will need to copy any Infragistics assemblies used as references, along with your custom assembly, to your Microsoft Office SharePoint Server. It is best to install the assemblies into the GAC to avoid Code Access Security exceptions. Because NetAdvantage for ASP.NET [CLR2] assemblies contain the necessary JavaScript files as embedded resources, creating a virtual directory for script files is not required; however, should you want to use custom images or CSS style sheets, you will want to set up a directory for those resources. You will also need to inform WSS of the directory and mark it for “Wildcard Inclusion.” You can use IIS to add a virtual directory, which will contain all of your resources, to your SharePoint site. Once you have added the virtual directory, use the SharePoint Central Administration page to include the directory.

 http://loch24/IT/Infragistics/GaugeImages/ctl00_m_g_00ddde17_f263_4e84_aec2_1637e41b8357_Gauge_none.png?t=128614872734091261

Is "ctl00_m_g_00ddde17_f263_4e84_aec2_1637e41b8357_Gauge_none.png" an actual file name that the control is trying to deploy?  Maybe there is no "image" assigned to this Gauge?

Remember, I haven't done ANYTHING in this test app, not binded any data, set any properties, etc.

Here is my source code (exatly like the one in the article on your site):

  Me._Gauge = New igGauge.UltraGauge()
  Me._Gauge.ID = "Gauge"
  Me._Gauge.DeploymentScenario.FilePath = "\ig_common\Images"
  Me._Grid = New igGrid.UltraWebGrid("Grid")
  Me.Controls.Add(Me._Gauge)
  Me.Controls.Add(Me._Grid)

End Sub

The code example was kept simple in order to separate the webpart specific logic, from the control specific logic.  The WebGauge has two main deployment scenarios, and the setup is critica in order to see results.  Deployment is covered in the help (http://help.infragistics.com/Help/NetAdvantage/NET/2008.2/CLR2.0/html/Gauge_Image_Deployment_in_WebGauge.html).  The main key is that there is a difference between deploymentScenario.FilePath and deploymentScenario.ImageUrl.  The two properties work together, so if you change one, you need to change the other.  In your case, setting the FilePath will force the gauge to save images to the \ig_common\Images folder.  However, the ImageUrl property still tells the gauge that images can be served up with a url of "GaugeImages/{uniqueImageName}.png  You need to adjust the ImageUrl to match what you've set for FilePath or vice-versa.  So, you should set the url to something like gauge.DeploymentScenario.ImageUrl="/ig_common/images/Gauge_#SEQNUM(100).jpg"  Also, the gauge.DeploymentScenario.FilePath takes a physical path, so setting it to "\ig_common\images" will actually set it to a subdirectory of the current page, which isn't what you want - you want a root level virtual directory.  Instead, use gauge.DeploymentScenario.FilePath=Page.MapPath("/ig_common/images");  That will turn the virtual directory into a physical path and save chart images there.  The DeploymentScenario isn't specific to SharePoint, so if you want to work in a classic ASP.NET web site to get a feel for working with these settings, it may be a little easier.

Hope this helps,

-Tony

Without a stacktrace it's very difficult to tell what the unexpected error is.  If you enable the callstack (http://www.sharepointblogs.com/michael/archive/2007/06/28/sharepoint-under-the-hood-see-real-error-description-and-callstack-stack-trace.aspx) it will help you see the underlying error so that you don't have to play a game of guess and check.  My guess is that either the "/ig_common/images" folder doesn't exist (it should be c:\inetpub\wwwroot\ig_common\images) - or the shareponit process doesn't have permissions to write files to that folder. 

Again, I would recommend you first start out using the gauge in a known environment like a standard ASP.NET web application, and then move that code into SharePoint - that way you can start to get a clearer picture of what's a gauge problem, and what's a sharepoint problem. 

One last solution you may want to look into is the SharePoint SmartPart which allows you to create declarative markup (user controls) as part of your sharepoint webpart.  The project is up on codeplex - http://www.codeplex.com/smartpart

-Tony