Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Apple releases OS X Lion 10.7.4 –
Full release notes:
- Resolve an issue in which the “Reopen windows when logging back in” setting is always enabled.
- Improve compatibility with certain British third-party USB keyboards.
- Addresses permission issues that may be caused if you use the Get Info inspector function “Apply to enclosed items…” on your home directory. For more information, see this article.
- Improve Internet sharing of PPPoE connections.
- Improve using a proxy auto-configuration (PAC) file.
- Address an issue that may prevent files from being saved to an SMB server.
- Improve printing to an SMB print queue.
- Improve performance when connecting to a WebDAV server.
- Enable automatic login for NIS accounts.
- Include RAW image compatibility for additional digital cameras.
- Improve the reliability of binding and logging into Active Directory accounts.
- The OS X Lion v10.7.4 Update includes Safari 5.1.6, which contains stability improvements.