Error: Cannot have multiple items selected in a DropDownList

Not too long ago, I created an ASP.NET website using Oracle (this is the same website as in an earlier post). On one of the administration pages, the item selected in some drop-down lists changed dynamically if items were deleted, but I was hit with the following error: Cannot have multiple items selected in a DropDownList. I was using ddlMyList.SelectedValue = someValue to change the selected item, but that wasn't working in this case. Here's how to fix this.

Problem: Website throws the error "Cannot have multiple items selected in a DropDownList" when trying to programmatically change the selected item using ddlMyList.SelectedValue = someValue.

Error: System.Data.OracleClient requires Oracle client software version 8.1.7 or greater

Recently, I had an assignment to create a custom CMS for an ASP.NET website (for my web development program). Now, everything worked fine on my development machine, on which I had Oracle client installed, but when I uploaded the website to my server, I got the yellow screen of death with the error below. Ideally, I'd be able to install the client, but that was not possible in my case. The key was to somehow set up the website to connect to Oracle without installing a client.

Problem: Website throws error "System.Data.OracleClient requires Oracle client software version 8.1.7 or greater" on live/production server. In my case, my hosting server did not allow me to install Oracle client, so what to do?