<p>I typically use URL rewriting to pass content IDs to my website, so this</p>

<pre><code> Foo.1.aspx 
</code></pre>

<p>rewrites to</p>

<pre><code> Foo.aspx?id=1
</code></pre>

<p>For a specific application I need to pass in multiple IDs to a single page, so I've rewritten things to accept this:</p>

<pre><code> Foo.1,2,3,4,5.aspx
</code></pre>

<p>This works fine in Cassini (the built-in ad hoc web server for Visual Studio) but gives me "Internet Explorer cannot display the webpage" when I try it on a live server running IIS. Is this an IIS limitation? Should I just use dashes or underscores instead of commas?</p>

The right way to
accept
multiple ids is like this:
```
```
Foo.aspx?id=1;id=2;id=3;id=4;id=5
```
```
Note that's just what the target is.  When re-writing urls, you can set your own rules to a certain extent for what you want the source to look like.
I had to learn this on StackOverflow, too.  See this question:
Split out ints from string