How to find out if we can open a bank account?

We are thinking of returning to France under auto-entrepreneur, as I think you may know. When I worked there as an Artisan 2005-8 I cannot remember making any formal declaration of cessation of business. Will this be a problem if I return and try and register as auto-entrepreneur in a different department?

Also, when we left and sold our house the French system should ensure that all debts are paid off with respect to mortgages etc. and then we as the vendors receive any balance that is remaining after all mortgage debts are paid off. We moved here to Ireland and after about 6 months we began to receive emails from Barclays (Barffimo) telling us that we owed them 1,000 euro somehow. We found this very strange as it is the responsibility of the Notaire to ensure all debts are cleared. So we ignored it because we felt they should be contacting the Notaire concerned as it was his responsibility to ensure any debts were cleared before giving us any profit from the sale. It all seemed very odd.

Now we are thinking of returning we are a little concerned that we may have ended up on some kind of Banking blacklist - through no fault of our own. My question is how can we find out? We cannot move back only to discover that when we try and open a bank account it is not possible.