Just put on a new 900 sq ft addition. I made what might be a very critical error. I did not use blueboard, but rather a mold resistant drywall in the bathroom and drywall in other areas. I found out that these are not good for plaster. Is there some sort of preping I can do to the wall before I plaster to allow it to stick?

Hi Dr Ping

You being in the US I presume by this quote,
you are refering to a "set coat" or "render coat", that is a thin coat of plaster over the entire wall.

Just getting termonology right. We all have a different way of expressing ourselves.

Here in Australia we rarely do a "set coat" over plasterboard, we just flush finish the joins.

In the Uk most plasterboard has a "set coat". You will find in the Uk they have no problem with the set coat sticking directly to the plasterboard or drywall. Neither will you.

No preparation is required except that the joins require taping with paper tape.

Cheers

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Also worth noting your "blueboard" is not what we call blueboard, our blueboard is 7.5mm compressed sheeting, yours is a wet area gypsum product...