The ASP.NET AJAX RadChart works like this:
1. When the page containing the control is created, a chart image is rendered and saved on the disk / in the session.
2. The server sends an HTML document containing an img
tag which has a source attribute set to something like "ChartImage.axd?ChartID=bd6589b0...".
3. When the client browser process this tag it requests the image from the server.
4. Next on the server the Chart Image HttpHandler is activated and tries to load this image from the disk/session. After it loads it it writes it in the HttpContext.Response.
5. The Chart Image HttpHandler tries to delete the image from the disk / session.
That said, the main suspect is the security policy on the TempImages folder, however from your post this doesn't seam to be the case.
Another case - a bit more complicated may be the following:
1) The chart control gets loaded and rendered (thus generating the image file).
2) However, the browser has turn off the option to load images, or some plugin is blocking the download.
3) As a consequence from (2) the HTTP Handler never loads up and never deletes the image from disk.
If the problem persists I suggest that you do one of the following:
1. Create your own daemon application that periodically deletes all the images in the folder older than eg. 5 minutes.
2. Write a custom HttpHandler and implement a custom strategy for handling these problems.This might be helpful, because you can log every step process, so you can more easily troubleshoot later if it is needed.
I hope this helps.
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