If they denied that claim for cause, such as fraud, then there is nothing you can do. If they did not have cause, you can try contacting the department of insurance in your state. That is of course, as long as you had comphrensive coverage on the policy. If you did not have coverage, they do not have to pay for anything.
Contact the insurance commissioner for that state and file complaint
Generally yes, it is called subrogation. Depending upon the circumstances as to WHY to coverage did not apply.
Then it's time for a lawsuit.
Let your insurance company/agent handle the claim--they will collect from the other insurance if there is a valid claim. You'll need a police report.
Once the insurance company has paid the claim for stolen items they become the legal owners of the items.
Read your policy
Stolen car that claim was paid off by the insurance company. The car was later recovered. Because the claim was already paid the car is owned by the insurance company and they will typically sale these at auction.
No, that wouldn't be a reason for claim denial. It may be a reason for them to investigate you for insurance fraud.
They will accept almost any claim, paying it is another matter.
You must have comprehensive coverage in order to recover on a claim from your insurance company if your vehicle is stolen. Liability only is just that, liability for your legal liability for damage or injuries to others.
A claim is a liability on part of the insurance company. If a customer makes a claim it means that the insurance company has to pay the customer for the amount is eligible to claim and hence it is a expenditure on the balance sheets of the insurance company.
The only step you have left is to sue the driver of the other vehicle. Keep in mind, it is your responsibility to prove that the other driver was at fault.