Hello, and welcome!
My name is ***** ***** I will be glad to help with your Safe question. I thank you for including your model and serial numbers and please note that the model number is *****SW3607, not C8W23607; I know it's difficult to read, on the safe. You will need to enter these exact numbers when you request your combination.
It sounds like you don't have your original combination, if your wife lost the regs. There is only one way to retrieve it, and that is from the manufacturer, Sentry. Combinations are never available online for your safety and protection. Follow the directions at the webpage, below, and if this is urgent, you can pay a small fee for expedited shipping and get your combination within 1-2 days:
Even though you believe your batteries are good, I would recommend changing them for new ones, again, just to be sure--sometimes, 'new' batteries sit on a shelf in the warehouse or a store and the power begins to drain. Use only alkaline or lithium for electronics (these last longer) and never rechargeable batteries. In addition, check that there is no corrosion (rust or leaked battery acid) in your battery holder and if you find some, clean it out well, with some rubbing alcohol and a Q-tip. Also, double check that your batteries are inserted correctly with the positive and negative poles in the right place.
Here is a downloadable copy of your owners manual; it will include everything except your combination, which came in your original one:
If the problem is not a lost combination, please let me know, and also tell me what you have tried so far, and I will be glad to help you further with more suggestions to get the safe open.
I wish you a very Happy Holiday season!
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