How to delete temporary files to free space in C: drive:

• Click on start and then run button
• Type %temp% then press enter
• In the new dialog box, press Ctrl+A to select all the temporary files listed.
• press Delete key or press shift+delete key

Note : If only delete key is press, all the files move to recycle bin, which is needed to be empty by right click then    
          empty recycle bin but if shift+delete is press it deletes directly without going to recycle bin