The problem is after the redirect to the other website, if the user then goes back to the original page, the first DropDownList is in its last state, but the second DropDownList is empty and to continue they must either select away from their last choice in the first DropDownList or refresh the page.
Ideally I would like to return the page and all controls to their last state, or make the page reset to as if it was accessed for the first time.
The ScriptManager history functionality could probably be used for this purpose, but a simple solution that worked for me was to disable all caching of the page, which results in the page being reset.
The following code might be a bit of overkill but does the job:
Response.Expires = 0;The answer came from this answer on ASP.NET forums.
Response.ExpiresAbsolute = DateTime.Now.AddYears(-2);
Response.CacheControl = "no-cache";
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If you are having intermittent problems sending email in .NET using System.Net.Mail consider switching libraries.
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As support ends for Microsoft Windows Server 2008 I have recently gone through migrating some websites to a new server running Windows Server 2016 and IIS 10 but some of the websites did not work.
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