Received InDesign file from a client to take and utilize some elements and add to the document design, etc. When I tried to open it would not let me -- gave me 2 lists of a number of plug-ins that my client has on their version of InDesign. Haven't upgraded anything on my InDesign in few years. I am working on iMac with OS X 10.4.11 system. What is available to me on my system.
That file was created in a later version of InDesign. You are now 6 versions out of date and saving back to CS3 is going to be nearly impossible.
To upgrade you’ll probably need a new computer.