Are you asking if you can e-file a 1040X (individual) or a business return. You state CO business returns cannot be e-filed, then you ask if 104X can be (don't know what a 104X is

I was asking if a CO 104X can be e-filed, not a 1040X (Individual). I already know a federal amended personal return can be e-filed.

CO 104X is and amended individual tax return.

Thank you.

did you check check the Box to file State Amended Returns and select Colorado on the Federal Information Worksheet in Part VII?

Yes, but had to uncheck it since I received a message saying that CO amended couldn't be e-filed and to paper file it.

Make sure you have Part VI, File state or city returns electronically checked and Part VII, State amended returns checked with Colorado in the box. Did you e-file the original return? Have you checked for any errors on the State side?

For anyone like me that came across this and it didn't answer the question.

You need to uncheck the file state return above in the normal e-file section VI - "Electronic Filing of Tax return Information" uncheck next to the  "File state or city returns electronically" BUT only after having selected to e-file an amended state return for Colorado in section VII then going to Colorado return and going to the bottom of the information section to see that indeed the program has checked the amended filing box.  At least that is what allowed for me to move forward with filing an amended CO 104x.  Once I unchecked the box in section VI and exited to the E-file center the line for the state return now said "CO Amended" in the Return Type section.

Hope this helps anyone who was lost for 20 minutes trying to figure this out.

Thank you for following up on this.

I'll use the steps you list the next time I have to file an amended CO tax return.

Have you had any luck with filing CO amended S Corps and Partnership tax returns?