Ubuntu update: BADSIG

หลายๆครั้งที่ ใช้ update manager จะขึ้น error เช่น

W: GPG error: http://archive.canonical.com intrepid Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key

W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used.GPG error: http://wine.budgetdedicated.com intrepid Release: The following signatures were invalid: BADSIG 58403026387EE263 Scott Ritchie


W: GPG error: http://security.ubuntu.com intrepid-security Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key

W: GPG error: http://packages.medibuntu.org intrepid Release: The following signatures were invalid: BADSIG 2EBC26B60C5A2783 Medibuntu Packaging Team

W: GPG error: http://us.archive.ubuntu.com intrepid Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key

W: GPG error: http://us.archive.ubuntu.com intrepid-updates Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key

W: GPG error: http://us.archive.ubuntu.com intrepid-backports Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key

W: Failed to fetch http://wine.budgetdedicated.com/apt/dists/intrepid/Release