Absolute Beginner needs help....

Hello, Whenever I save a file to my desktop
and then click to open the file
, or if I open the file after including it as an attachment in an email, the address in the url Text field info changes - for example to

file:///CUsers/Maria%20Smith.mariasmith-PC/Desktop/My%20Stuff/My%20%20Documents/The%20electronic%20File/Hp%20dv6t%20series%20%20$624.99.htm


The file either doesn't open or doesn't exactly match the page I saved. A message comes up that says: * Firefox can't find the file at file:///CUsers/Joe%20Smith.joesmith-PC/Desktop/My%20Stuff/My%20%20Documents/The%20electronic%20File/Hp%20dv6t%20series%20%20$624.99.htm or

* Check the file name for capitalization or other typing errors.

* Check to see if the file was moved, renamed or deleted.

What do I need to do in order to correct this problem? Any help would be greatly appreciated. Thank You.