I did not get any hits on searching the forum for an error 76. I opened a new instance of SGP V 18.104.22.168 and connected my mount. I then opened an existing FITS file of NGC891. I right-clicked on the image and clicked on plate solve. I chose solve as this error does not occur when I choose blind solve. I then entered my pixel scale and after clicking on solve, I got the error 76. Blind solve works fine at plate solve.
pls let me know if you need additional information Jared.
Any help is appreciated.