Did your father have a will? If your father died without a will (aka intestate) the probate court is in charge of distributing his property and assets. State laws vary, so you'll need to review the estate and probate laws where he resided.

The probate court can appoint an administrator (no will) or an executor (will) to settle the estate. The executor has to notify heirs and beneficiaries, so you should contact him or her, assuming one exists. If not, you may need to petition the court, especially if you are the only relative or potential beneficiary.

Have you contacted his place of employment? I think it makes sense to call them. They should tell you what you need to find out whether or not you are listed as a beneficiary on the 401K account, insurance, and profit sharing accounts.

If you are listed as a beneficiary of his 401K account the money should transfer to you fairly easily as a transfer on death account, assuming dad has no spouse. You need to call the company he worked for to find out how to proceed. Banks require beneficiaries to provide an original copy of a death certificate so it's reasonable to think you will need to have a one to access the 401K and other accounts.

Even if you had access to your dad's home and found a copy of his 401K paperwork it doesn't mean that it's the most current copy. Call the workplace. Talk to the executor.

Hope that helps provide some direction.

401k funds generally have a named beneficiary and are usually distributed outside of probate and paid directly to the beneficiary. Who is it that has access to your father's papers that isn't allowing you to access any information?

If your father has a spouse, the spouse is the default beneficiary of a 401k, it's a federal law. The only way the spouse would not be the beneficiary is if the spouse signed a waiver giving up that right.