I can't get out of a login loop of a particular admin user. After entering the password the login screen is shown again after about a minute. Other users work fine. It started happening after a simple reboot.

Can you please help me? Thank you!

Tried to no avail:

• Change the password
• Remove the password
• Repair disk (no errors)
• Boot in safe mode
• Reinstall Snow Leopard and updating to 10.6.6
• Remove content of ~/Library/Caches
• Removed content of ~/Library/Preferences
• Replaced /etc/authorization with Install DVD copy

The system.log mentions a crash report. I'm including both below.

system.log

Jan 8 02:43:30 loginwindow218: Login Window - Returned from Security Agent
Jan 8 02:43:30 loginwindow218: USER_PROCESS: 218 console
Jan 8 02:44:42 kernel[0]: 
Jan 8 02:44:43: --- last message repeated 1 time ---
Jan 8 02:44:43 com.apple.launchd[1] (com.apple.loginwindow218): Job appears to have crashed: Bus error
Jan 8 02:44:43 com.apple.UserEventAgent-LoginWindow223: ALF error: cannot find useragent 1102
Jan 8 02:44:43 com.apple.UserEventAgent-LoginWindow223: plugin.UserEventAgentFactory: called with typeID=FC86416D-6164-2070-726F-70735C216EC0
Jan 8 02:44:43 /System/Library/CoreServices/loginwindow.app/Contents/MacOS/loginwindow233: Login Window Application Started
Jan 8 02:44:43 SecurityAgent228: CGSShutdownServerConnections: Detaching application from window server
Jan 8 02:44:43 com.apple.ReportCrash.Root232: 2011-01-08 02:44:43.936 ReportCrash232:2903 Saved crash report for loginwindow218 version ??? (???) to /Library/Logs/DiagnosticReports/loginwindow_2011-01-08-024443_localhost.crash
Jan 8 02:44:44 SecurityAgent228: MIG: server died: CGSReleaseShmem : Cannot release shared memory
Jan 8 02:44:44 SecurityAgent228: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged.
Jan 8 02:44:44 SecurityAgent228: CGSDisplayServerShutdown: Detaching display subsystem from window server
Jan 8 02:44:44 SecurityAgent228: HIToolbox: received notification of WindowServer event port death.
Jan 8 02:44:44 SecurityAgent228: port matched the WindowServer port created in BindCGSToRunLoop
Jan 8 02:44:44 loginwindow233: Login Window Started Security Agent
Jan 8 02:44:44 WindowServer234: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged.
Jan 8 02:44:44 com.apple.WindowServer234: Sat Jan 8 02:44:44 .local WindowServer234 <Error>: kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged.
Jan 8 02:44:54 SecurityAgent243: NSSecureTextFieldCell detected a field editor ((null)) that is not a NSTextView subclass designed to work with the cell. Ignoring...

Crash report

Process: loginwindow 218
Path: /System/Library/CoreServices/loginwindow.app/Contents/MacOS/loginwindow
Identifier: loginwindow
Version: ??? (???)
Code Type: X86-64 (Native)
Parent Process: launchd [1]

Date/Time: 2011-01-08 02:44:42.748 +0100
OS Version: Mac OS X 10.6.6 (10J567)
Report Version: 6

Exception Type: EXC_BAD_ACCESS (SIGBUS)
Exception Codes: 0x000000000000000a, 0x000000010075b000
Crashed Thread: 0 Dispatch queue: com.apple.main-thread

Thread 0 Crashed: Dispatch queue: com.apple.main-thread
0 com.apple.security 0x00007fff801c6e8b Security::ReadSection::at(unsigned int) const + 25
1 com.apple.security 0x00007fff801c632f Security::DbVersion::open() + 123
2 com.apple.security 0x00007fff801c5e41 Security::DbVersion::DbVersion(Security::AppleDatabase const&, Security::RefPointer<Security::AtomicBufferedFile> const&) + 179
3 com.apple.security 0x00007fff801c594e Security::DbModifier::getDbVersion(bool) + 330
4 com.apple.security 0x00007fff801c57f5 Security::DbModifier::openDatabase() + 33
5 com.apple.security 0x00007fff801c5439 Security::Database::_dbOpen(Security::DatabaseSession&, unsigned int, Security::AccessCredentials const*, void const*) + 221
6 com.apple.security 0x00007fff801c4841 Security::DatabaseManager::dbOpen(Security::DatabaseSession&, Security::DbName const&, unsigned int, Security::AccessCredentials const*, void const*) + 77
7 com.apple.security 0x00007fff801c4723 Security::DatabaseSession::DbOpen(char const*, cssm_net_address const*, unsigned int, Security::AccessCredentials const*, void const*, long&) + 285
8 com.apple.security 0x00007fff801d8414 cssm_DbOpen(long, char const*, cssm_net_address const*, unsigned int, cssm_access_credentials const*, void const*, long*) + 108
9 com.apple.security 0x00007fff801d7fba CSSM_DL_DbOpen + 106
10 com.apple.security 0x00007fff801d62f6 Security::CssmClient::DbImpl::open() + 162
11 com.apple.security 0x00007fff801d8977 SSDatabaseImpl::open(Security::DLDbIdentifier const&) + 53
12 com.apple.security 0x00007fff801d8715 SSDLSession::DbOpen(char const*, cssm_net_address const*, unsigned int, Security::AccessCredentials const*, void const*, long&) + 263
13 com.apple.security 0x00007fff801d8414 cssm_DbOpen(long, char const*, cssm_net_address const*, unsigned int, cssm_access_credentials const*, void const*, long*) + 108
14 com.apple.security 0x00007fff801d7fba CSSM_DL_DbOpen + 106
15 com.apple.security 0x00007fff801d62f6 Security::CssmClient::DbImpl::open() + 162
16 com.apple.security 0x00007fff802fa786 Security::CssmClient::DbImpl::unlock(cssm_data const&) + 28
17 com.apple.security 0x00007fff80275b5d Security::KeychainCore::KeychainImpl::unlock(Security::CssmData const&) + 89
18 com.apple.security 0x00007fff80291a06 Security::KeychainCore::StorageManager::login(unsigned int, void const*, unsigned int, void const*) + 3336
19 com.apple.security 0x00007fff802854d3 SecKeychainLogin + 91
20 com.apple.loginwindow 0x000000010000dfc5 0x100000000 + 57285
21 com.apple.loginwindow 0x000000010000cfb4 0x100000000 + 53172
22 com.apple.Foundation 0x00007fff8721e44f __NSThreadPerformPerform + 219
23 com.apple.CoreFoundation 0x00007fff82627401 __CFRunLoopDoSources0 + 1361
24 com.apple.CoreFoundation 0x00007fff826255f9 __CFRunLoopRun + 873
25 com.apple.CoreFoundation 0x00007fff82624dbf CFRunLoopRunSpecific + 575
26 com.apple.HIToolbox 0x00007fff8444493a RunCurrentEventLoopInMode + 333
27 com.apple.HIToolbox 0x00007fff8444473f ReceiveNextEventCommon + 310
28 com.apple.HIToolbox 0x00007fff844445f8 BlockUntilNextEventMatchingListInMode + 59
29 com.apple.AppKit 0x00007fff80b01e64 _DPSNextEvent + 718
30 com.apple.AppKit 0x00007fff80b017a9 -NSApplication nextEventMatchingMask:untilDate:inMode:dequeue: + 155
31 com.apple.AppKit 0x00007fff80ac748b -NSApplication run + 395
32 com.apple.loginwindow 0x0000000100004b16 0x100000000 + 19222
33 com.apple.loginwindow 0x0000000100004580 0x100000000 + 17792

Thread 1: Dispatch queue: com.apple.libdispatch-manager
0 libSystem.B.dylib 0x00007fff8755216a kevent + 10
1 libSystem.B.dylib 0x00007fff8755403d _dispatch_mgr_invoke + 154
2 libSystem.B.dylib 0x00007fff87553d14 _dispatch_queue_invoke + 185
3 libSystem.B.dylib 0x00007fff8755383e _dispatch_worker_thread2 + 252
4 libSystem.B.dylib 0x00007fff87553168 _pthread_wqthread + 353
5 libSystem.B.dylib 0x00007fff87553005 start_wqthread + 13

Thread 0 crashed with X86 Thread State (64-bit):
rax: 0x000000010075b000 rbx: 0x00007fff5fbfd990 rcx: 0x00007fff875439da rdx: 0x0000000000000000
rdi: 0x00007fff5fbfd990 rsi: 0x0000000000000000 rbp: 0x00007fff5fbfd5d0 rsp: 0x00007fff5fbfd5d0
r8: 0x0000000000000007 r9: 0x0000000000000000 r10: 0x00007fff8753beda r11: 0x0000000000000202
r12: 0x0000000100133e78 r13: 0x00007fff5fbfda50 r14: 0x00007fff5fbfda50 r15: 0x00007fff5fbfdaa0
rip: 0x00007fff801c6e8b rfl: 0x0000000000010287 cr2: 0x000000010075b000