This is a widely-known, old issue with the .NET Webbrowser control.

Summary: Having the .NET webbrowser control Navigate to a page increases memory usage that is never freed.

Reproduce the memory leak: Add a WebBrowser control to a form. Use it to Navigate to whatever pages you'd like. about:blank works, scrolling down on Google Images until your usage is 100MB+ and then browsing elsewhere to notice barely any of that memory is freed is a more dramatic demonstration.

My current requirements for an application include running it for long periods of time, displaying a limited IE7 browser window. Running IE7 itself with some bastard setup of hooks, BHOs and group policies isn't desired either, although that's looking like the fallback at this time. Embedding a browser into a Windows Forms application is. Using a different browser base is not an available option for me. IE7 is required.

Previous threads and articles relating to this known memory leak:

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