Working where I do gives me the opportunity to work with the latest and greatest of technologies.  Exchange 2007 is, in my opinion, a huge improvement over 2003 in terms of speed.  However, it moved too far away from the familiar GUI (like vista did), and therefore some usability has suffered.

Because Exchange 2007 requires 64 bit processors (or at the very least an Intel processor that emulates 64 bit technology), Windows Server 2003 X64 is needed. This means that Exchange will use up as much RAM as it wants to (10 out of 12GB on our server). It also means that .net 1 and .net 1.1 DO NOT work well with it. There are scripts that enable IIS to support 32 bit processes, but who wants to muck up the works with 32 bit and 64 bit processes fighting for resources?

If you accidentally install the Windows update hotfix .net 1.1 on your exchange server (I know I did), then it will automatically convert your nice 64 bit Exchange server into a 32bit mixed-mode Exchange server. Which might not be bad, except for the fact that IIS doesn’t like to mix modes. And that takes me to the point of all this writing – IIS does NOT like 32bit and 64bit.

When the hotfix made Exchange go into mixed-mode, IIS freaked out and stopped supporting OWA (outlook web access). It hosted a site called “Service Unavailable”. Not very creative. And through lots of searching, I came upon a set of instructions that is quite easy and works every time I replicate the issue.

1.) Uninstall Hotfix 1.1. If you really need .net 1 support, you’ll have to look elsewhere. .net2 works just fine. It’ll ask you to reboot the server, which sucks.
2.) Uninstall .net 1.0. Read above if you really require .net 1 support.
3.) On your exchange server, run this from the command line: “%SYSTEMROOT%\Microsoft.NET\Framework64\v2.0.50727\aspnet_regiis.exe -i”
If you get an error indicating that IIS is in 32 bit mode, go to step 4, otherwise go to step 5.
4.) ONLY TYPE THIS IF YOU GOT AN ERROR. “cscript c:\inetpub\adminscripts\adsutil.vbs SET /w3svc/AppPools/Enable32BitAppOnWin64 False”
This will make it so you are in a pure 64Bit environment again. After a couple minutes, go to Step 3 and run that command again (it will pass this time).
5.) Restart IIS. Check your OWA or Exchange web access.

Here’s the full error:
The Login User Interface DLL CSGina.dll failed to load. Contact your system administrator to replace the DLL, or restore the original DLL.

This happens when you uninstall, and sometimes install, the Cisco VPN client. Cisco VPN client adds a registry key that disables fast user switching and loads the client before booting into Windows.

The fix below requires editing your registry files. If you have no idea what a registry file is, you probably shouldn’t be editing them. If you edit incorrectly your computer may refuse to boot. Here’s the quick fix:

1.) Reboot the machine
2.) Press F8 to load up the boot options menu for Windows
3.) Select Safe Mode and then select your Windows Installation
4.) After Windows loads into safe mode, it’ll ask if you want to continue working in Safe Mode. Select Yes.
5.) Start >> Run >> “regedit” (without the quotes). Press Enter.
6.) Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\CurrentVersion\Winlogon
7.) Look for the GinaDLL Key
8.) Select and delete this key. DO NOT delete the entire Winlogon folder of keys.
9.) Close Regedit and reboot the machine

***EDIT***
This is actually the most popular post on it.thelibrarie.com! Awesome!

BSOD = Blue Screen Of Death

STOP: 0x0000000A
IRQL_NOT_LESS_OR_EQUAL
This Stop error, which can be caused by either software or hardware, indicates that a kernel-mode process or driver attempted to access a memory location it did not have permission to access or a memory location that exists at a kernel interrupt request level (IRQL) that was too high. A kernel-mode process can access other only processes that have an IRQL that’s equal to or lower than its own.

STOP: 0x0000001E
KMODE_EXCEPTION_NOT_HANDLED
This Stop error indicates that indicates that the Windows XP kernel detected an illegal or unknown processor instruction. The problems that cause this Stop error can be either software or hardware related and result from invalid memory and access violations, which are intercepted by Windows’ default error handler if error-handling routines are not present in the code itself.

STOP: 0x00000050
PAGE_FAULT_IN_NONPAGED_AREA
This Stop error indicates that requested data was not in memory. The system generates an exception error when using a reference to an invalid system memory address. Defective memory (including main memory, L2 RAM cache, video RAM) or incompatible software (including remote control and antivirus software) might cause this Stop error.

STOP: 0x0000007B
INACCESSIBLE_BOOT_DEVICE
This Stop error indicates that Windows XP has lost access to the system partition or boot volume during the startup process. Installing incorrect device drivers when installing or upgrading storage adapter hardware typically causes this Stop error. This error could also indicate a possible virus infection.

STOP: 0x0000007F
UNEXPECTED_KERNEL_MODE_TRAP
This Stop error indicates a hardware problem resulting from mismatched memory, defective memory, a malfunctioning CPU, or a fan failure that’s causing overheating.

STOP: 0x0000009F
DRIVER_POWER_STATE_FAILURE
This Stop error indicates that a driver is in an inconsistent or invalid power state. This Stop error typically occurs during events that involve power state transitions, such as shutting down, or moving in or out of standby or hibernate mode.

STOP: 0x000000D1
DRIVER_IRQL_NOT_LESS_OR_EQUAL
This Stop error indicates that the system attempted to access pageable memory using a kernel process IRQL that was too high. The most typical cause is a bad device driver (one that uses improper addresses). It can also be caused by faulty or mismatched RAM or a damaged pagefile.

STOP: 0x000000EA
THREAD_STUCK_IN_DEVICE_DRIVER
This Stop error indicates that a device driver problem is causing the system to pause indefinitely. Typically, this problem is caused by a display driver waiting for the video hardware to enter an idle state. This might indicate a hardware problem with the video adapter or a faulty video driver.

STOP: 0x00000024
NTFS_FILE_SYSTEM
This Stop error indicates that a problem occurred within Ntfs.sys, the driver file that allows the system to read and write to drives formatted with the NTFS file system. (A similar Stop message, 0x00000023, exists for the file allocation table [FAT16 or FAT32)] file systems.)

STOP: 0xC0000218
UNKNOWN_HARD_ERROR
This Stop error indicates that a necessary registry hive file could not be loaded. The file may be corrupt or missing. The registry file may have been corrupted due to hard disk corruption or some other hardware problem. A driver may have corrupted the registry data while loading into memory or the memory where the registry is loading may have a parity error.

STOP: 0xC0000221
STATUS_IMAGE_CHECKSUM_MISMATCH
This Stop message indicates driver, system file, or disk corruption problems (such as a damaged paging file). Faulty memory hardware can also cause this Stop message to appear.

STOP: 0x0000008e
This is usually an issue with RAM, but it all depends on the system. Most often it will happen with Windows XP SP2.