I have an Aspx page with no .cs file. This page is using a dll file which is already in the GAC of my machine. I have a new version of this dll, but I don't want to change anything in the GAC. Can I make this aspx page load the dll from my bin directory and override the GAC?
Yes. Just put new assembly to folder where your application binaries are and use assembly redirection Assembly Redirection
And make sure your assembly version has changed.