I have question regarding HTTP Header that SharePoint returns for some files such as init.js, core.js, etc. I check using some plugin on Firefox, it seems that SharePoint always sets cache-control automatically, like cache-control: no-cache, max-age:31xxxxxxxx. I try to control this by adding HTTP Header in IIS, set the cache-control: max-age:3600,no-check. And after adding this, the HTTP header for these files become: cache-control: no-cache, max-age: 31xxxxxx, max-age:3600,no-check Some page like webresource.axd might have different attribute: cache-control: private, max-age:3600,no-check I believe any browser will not cache these files with this cache-control, which means that super large file like core.js will be downloaded every request. Any advice or idea on this?