If you have previously filed a Chapter 7 case and received a discharge, you cannot receive a discharge in another Chapter 7 case that is filed less than 8 years later. This actually is thought to originate with the Bible in Deuteronomy 15, which states "At the end of every seven years you shall grant a release of debts". So while the Bible says 7 years, Congress seemed to think that God was going a little to easy on people, so they upped it to 8 years.
If you are in this situation, you have two options: 1) Wait for the 8 years to pass and then file a Chapter 7 bankruptcy, or 2) file a Chapter 13 bankruptcy which does not have this limitation. If you do end up filing a Chapter 13 bankruptcy, you can dismiss your case and file a Chapter 7 bankruptcy once the 8 years is up. However, for some people, Chapter 13 bankruptcy can be the better option even if you are eligible to file a Chapter 7 bankruptcy. I had a case where my client needed to file before the 8 years was up, so we filed his case as a bankruptcy under Chapter 13. Since Chapter 13 bankruptcy can modify secured debts, like a car loan, we were able to include and lower his car payment. His Chapter 13 payment to the bankruptcy trustee was less than what his car payment was prior to filing, so he stayed in the Chapter 13 even after the 8 years was up and he was eligible for Chapter 7. A bankruptcy case filed under Chapter 13 is going to be complex and difficult, but it can provide some major advantages.