Fixing the 'The URL-encoded form data' is not valid. Error

Symptom

When using certain administration screens with very large page sizes, you might come across (rarely) the following error message:

The messages may include the following:

The URL-encoded form data is not valid

The maximum number of form, query string, or posted file items has already been read from the request. To change the maximum allowed request collection count its current value of 2000, change the "aspnet:MaxHttpCollectionKeys" setting.

Solution

Locate the Spira web.config file in your installation and open it up in a text editor. Then find the following section:

	<appSettings>
		<add key="aspnet:MaxHttpCollectionKeys" value="2000" />
        ...
        ...
	</appSettings>

and change the value of 2000 to a larger value, for example:

	<appSettings>
		<add key="aspnet:MaxHttpCollectionKeys" value="10000" />
        ...
        ...
	</appSettings>

and that should fix the issue.