Following other problems (see Link to pdf file in this forum) I uninstalled,then reinstalled SilverStripe. Now when I log-in, there is a brief flash of my home page, then I get a page with only the SilverStripe logo on it. Pretty, but useless. Clicking the back arrow on my browser returns me to the log-in page. I've tryed a different brower and clearing the cache, but same result. Any ideas? I'm not a web developer - I only have some html and css knowledge, so please keep any reply as non technical as possible

Note: SilverStripe was installed in the space provided by my Host, using cPanel and Installatron. My Host Support is, so far, silent on this problem

Could be a cache related problem (this is common on shared hosting). You could try adding a silverstripe-cache folder in the webroot and running a flush which will store the cache in this new folder and can get around shared hosting restrictions on the server /tmp folder.

It is important to load the admin with the web console open on the networking tab too. This is usually caused by a javascript issue, something that will show either in the console (as an error), or in the networking tab (as eg. 500, etc.).
Hopefully this will provide more information as to what could be going wrong.

If nothing useful is shown, ensure to load the site when it is in dev mode.
http://docs.silverstripe.org/en/getting_started/environment_management/

Well, my Host Support spent some time on this and managed to restore normal operation - except that the image/pdf loading problem continued. My solution? Abandon SilverStripe and rebuild using Wordpress. But thanks to those who responded - it's appreciated that you took the trouble to offer advice.