"compatibility" in Win7 and/or Win10?

   I have this program that was made for Win95 and never "upgraded" for 
the tape printer it was made for.
   It installs and runs without any special additions whatsoever in all 
OSes from Win95 thru and including XP.

   However, using Administrator mode and compatibility attempts, i get 
the following puzzling error message "There is not enough memory to 
execute that command".

   One of the compatibility mode choices is XP SP3, and i have used the 
program in XPSP3 for many years without any fuss, special additions 
whatsoever.

   The only thing i can think of, is the fact that the program uses 
COM1: for communication to the printer.

   For Win7, i use the same physical machine as for XPSP3.
   For Win10 i can only use the Lenovo.  No DVD came with it and the DVD 
i got from the vendor after complaint, was a Dell with following text on it:
"Operating System" , "Already installed on your computer" , "Use this 
disc only to reinstall the operating system on a Dell computer", "This 
disc is not for reinstallation of programs or drivers".

   I tried to use it to install on a blank HD; nogo.

   So, after this mind-numbing passel of info, do you have any 
suggestions to get it working in Win7?


     Thanks.