错误CS0103：当前上下文中不存在名称“txtReferralCode”

I'm about ready to pull my hair out over this. I'm working on an ASP.NET 2.0 website in VS2010 and I'm getting the error you see in the title. The error only appears when I attempt to publish the website. If I simply right click the aspx file that it's in and click "View in Browser" it works perfectly fine. It also works fine if I run the file in debug mode from VS2010. There are other asp controls in the code that work perfectly fine, but for whatever reason, the one I've added has a problem.I'm about ready to pull my hair out over this.