In the u. s., if a consumer finds a problem on her credit report, she must first send a letter to the credit-reporting agency. under federal law, how many days does the agency have to investigate and respond to the alleged inaccuracy and issue a corrected report?

Unless they consider the report false, the agency has 30 days to investigate the claim. In addition to the investigation, any relevant data that was reported to them must also be forwarded to the organization that they get information from. If information is deemed inaccurate then all three credit reporting companies must be notified so that your information can be corrected.