my adobe acrobat 7 professional will not open in 10.11.3

No Mac software made before Intel Macs (around 2003) can run on Mac OS 10.7 or later. This is a decision made by Apple, though of course Adobe would be very happy with it.

OSX 10.11.3??

If so, then it is no surprise; Acrobat 7 is too old, and has components no longer supported since about OSX 10.9.

As there is no upgrade path (as far as I know), you'd have to get Acrobat DC (either as a permanent license or as a subscription).

Hope this can help.