It always has worked before, but now every time I try to open a pps file, I get the mesage: "Command line option Syntax error. Type Command /? for help." And when I do that, I get this:

starts a new instance of the MS/DOS command interpreter.
[[drive:]path] [drive] [E:nnnnn] [/P] [/C string] [/MSG]

[[driveath] specifies the directory containing COMMAND.COM file
[device] specifies the device to use for command input and output
[/E:nnnnn] makes the new command interpreter permanent (can't exist)
[/C string] carries out the command specified by string. and then stops
[/MSG] specifies that all error messages be stored in memory. You need to specify /P with this switch

i HAVE NO IDEA OF WHICH ONE TO PICK IN MY SITUATION.

Can someone help me get to view my pps files?