Request for Computer Assistance

This is something different — not economics- but I need assistance.

I have a computer problem, but I don’t even know how to search for help on the web.

I write with a 30 year old DOS program.  Yes, but it is the best writing tool I know.  Something happened, so that the non-alphanumeric characters almost all appear as a little box.  Look at the one near entry 735.  This does not happen with the DOS screen is maximized.

In any case, the little boxes replace characters I need to recognize, besides the line feed/carriage return that the 735 box represents.

Can I fix this in the registry; can I repair the whole cmd.com program?

Any help would be appreciated.  Even if you can’t help, maybe you can tell me how search for help.  I tried Google, but nothing I entered was remotely useful.

Thanks

DOS problem