Once you file any bankruptcy, it will stay on your credit report for 10 years. The fact that the bankruptcy did not go through doesn't prevent the truthful reporting that the bankruptcy was filed, and federal law allows this Bankruptcy to be reported for 10 years. Hope this perspective helps!
The filing of the bankruptcy triggers the credit report entry. The outcome of the bankruptcy (discharged, dismissed, denied, etc) is largely irrelevant. Bankruptcy can stay on your credit report for 10 years. Your credit report can contain true and accurate information about. If you filed bankruptcy, that fact can be reported. However, if the bankruptcy is that old, it really shouldn't be affecting your credit or your ability to buy a house.
As for the joint account, you need to dispute that bankruptcy entry with the credit reporting agencies.
I agree with the previous answers. However, most people recover from a bankruptcy discharge within a few years, they even start receiving credit card offers after 6 months. In your case because your bankruptcy was dismissed and not discharged, your outstanding debt is probably what is impacting your credit. In many cases, collection and charge off accounts will drastically affect a person's credit file. You should consult with a law firm in your area that will review your credit report to make sure these old debts are reporting correctly as closed accounts and make sure you don't have any outstanding liability. You should also consult with an attorney in your area to figure out your financial liability for the account your sister is trying to discharge through bankruptcy. Good luck and I hope this was useful!
NOTE: This Answer does not constitute legal advice. Every case is fact specific. To render a legal opinion, an attorney must engage in a consultation with a prospective client and review any pertinent documents. This communication does not create an attorney-client relationship with Attorney Rochelle N Belnap or Belnap & Forbes, PLLC.