|What's the URL of your website? The server has a list of files that set the order of priorities to index pages. For example, index.htm, index.html, index.php, default.html, etc. Installing and later removing WordPress won't affect this priorities list, so I'm curious to see your directory and look for a problem.|
This article won't solve your problem, but it's a good idea to hide directory indexes from people looking for security vulnerabilities. After your problem is solved, hide directory indexes:
Apologies if I don't respond to your reply immediately. I don't check this site daily, but you're welcome to PM me as a reminder.