Painting - Restaining previously stained oak door

I have sanded down an oak door to bare wood, except for moldings which are too difficult to sand by hand. Some of the old lacquer finish remains. I want to stain the door darker but I am concerned that any new stain and finish will not adhere to the existing lacquer. One of the waterborn poly/stains I tried reacted to the lacquer residue and looks like crap. Do I have to strip away all the lacquer or is there an easier way to get the door stained down? If I do have to strip the lacquer, any product recommendations? Thank for any help...I'm getting desperate!

Welcome to the forums Andy!

Are you sure the current finish is lacquer? That would be unusual - varnish or poly is the norm.

Lacquer can be disolved and washed off with lacquer thinner.

Usually you can apply an oil finish over most lacquers without any issues. Restaining wood can be difficult. The wood needs to be raw to accept the stain and it is hard to remove all traces of the original finish.

Thank you for the Welcome Mat - I hope to make great use of it, wearing it very thin.

I'm not 100% sure the finish is lacquer but that seems to be the most logical. The door is on a tract home and all the doors on the estate are thae same. The seem to be factory pre-finished and lacquer would typically be applied because of its fast drying capabilities at the manufacturer. The kitchen cabinets are similarly finished and I found that finish also re-acted when I applied a light coat of polyurethane. So, lacquer, or possibly shellac, is likely. It could be varnish but I wouldn't have thought that would have reacted to the new waterborn poly. which I have just tried...without success.
Thanks for your reply.