If you are still running on Joomla 1.7.x, then its time to upgrade it to Joomla 2.5.xx latest version. In order to do it, the direct FIND UPDATES > INSTALL UPDATES method is not recommended, since it has broken many websites in the past. So, the best way to upgrade to the latest version is by getting the 2.5.0 Beta Update Package first.
Download Joomla 2.5.0 Beta Update Package
One that has been downloaded, unzip it and upload to your website root folder from the FTP manager. When it asks to overwrite, just press YES and proceed.
Now download the latest Joomla 2.5.x package (as per June 20th 2013, the latest is 2.5.11) and upload the files to the root folder and agree to over write the files.
Download Joomla 2.5.11 Stable Full Package