Why won't my page display unless I put an .html at the end of URL?

For some reason after transferring to a new server my invoices page and script aren't working. When a customer enters his information it is put in the database and it creates an invoice like so:

/Invoices/JohnDoe 10100188

However the URL should open up a nice invoice page with all the info for the order, instead I get a 404 Error now. Nothing has changed with the script or databases. We simply moved them to a new server and all开发者_开发百科 the included files. What's even stranger is that when you add .html to the end of JohnDoe 10100188 it will load the page. I don't know why but do I need to make my script add .html at the end now? It is confusing to me why this won't work now.. I was hoping someone had a similar problem and could help me out. I would be greatly appreciative!

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I'm not too familiar with Apache, but my guess would be that there's a configuration setting where you can set a default file extension for the case when one is not supplied.

Could be in .htaccess, or one of the Apache config files.