The following error will occur when you have a Comma (,) in your URL.

To use a comma in your IIS Website URL, you must have the URL Rewrite module installed on the IIS Server and running on the website.

The following code will allow your website to run with a comma.
Inside your web.config file, add the following.

(Change the MainName to the name of your Structure.
Example: Site.aspx?Main.aspx&Date=Jan_30,_1973&Page=My_Birthdate
MainName = Folder)

In the URL Rewrite, we can create a pattern that allows certain characters to be allowed in the URL
The example below shows how to use the comma in the URL String.
-,-
The full pattern is this. (This is what is used here on CFFCS.COM.)
([_0-9a-z-(-)-,-]+)
It is used only in the [Date] column.
(This can be used throughout all columns and does not just have to be used in a designated column)

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<system.webServer>
        <rewrite>
            <rules>	
		<clear /> <!-- At the top ONLY! -->
<rule name="MainName" stopProcessing="true">
    <match url="MainName/([_0-9a-z-(-)-,-]+)/([_0-9a-z-(-)]+)" />
    <action type="Rewrite" url="Site.aspx?Date={R:1}&Page={R:2}" appendQueryString="true" />
</rule>
<!-- Add all additional Rules here. All Rules must have their own <rule name>-->
            </rules>
        </rewrite>
    </system.webServer>
</configuration>