I loaded a clean install to the server for 4.5.3. I can access the host and admin accounts. Any changes I attempt to make I get a 'WebForm_PostBackOptions' is undefined error. I read through all the post suggestions. I have commented out in the web.config file the compression. I have excluded webresource.axd in the Compression file. I have deleted my cache, closed my browser, reopened, and I still get the error message for any changes I attempt to do. I cannot exclude it in Host settings, as I get the error message. No changes I attempt to make anywhere will keep, without receiving the error message. Does anyone have a suggestion as to what will work? I have been trying for two weeks to get anything to install correctly. Help and advice is greatly appreciated.

Thank you for the help. My site is hosted on a server. On my site settings in IIS, the .axd file was still mapped to .Net 1.1. My service provider fixed and my site can now edit and update. I appreciate the quick response and the information. It's small tidbits like this that help out when it's not found in the posts. Thanks!!!