Thinking about moving back home to Mass & have a question about excise tax

[intheflow]

I moved out of Massachusetts in 2001 to attend grad school in Colorado. Had no intention of ever moving back but now that my first grandchild has been born in Springfield, I am seriously reconsidering.

Here's my question, though: I think I left an excise bill unpaid. I didn't register my car in Colorado until 2004 (when I made the decision to stay here after grad school). How long do those taxes and charges remain on the record? How long do they seek collections? I imagine I could potentially owe thousands of dollars and that thought alone might keep me from returning home.

Anyone have any idea or experience with this?