To enable PAE mode, you have to add PAE to the boot entry in the BCD file. Open an elevated command prompt. Type BCDEDIT /SET PAE ForceEnable

Refer "More information" section...

To enable PAE, use the /PAE switch in the Boot.ini file. Here is more info on that

You are trying to install a service pack SQL Server 2008 on an instance running SQL Server 2008 R2.

10.5.1600.1 = SQL Server 2008 R2 RTM is the one that is...

Run sp_helpdb and you would notice that the Database Owner for that database is NULL. Running sp_changedbowner 'OwnerName' would fix this issue. I had a similar issue and posted about...

Run a profiler trace with the event "Audit Login Failed" selected. The trace should give you the Application Name with which the login is trying to connect

Double click the file and open it with C:\WINDOWS\SYSTEM32\REGSVR32.EXE

Missed to state that you need to register that DLL using REGSVR32.exe (located under c:\windows\system32)

AFAIK PAE switch is not enabled by default. This option is also applicable to Windows 2008. Please refer this

You may try the following.

Copy the existing BatchParser.dll to a safe location

Locate an instance running the same build of SQL Server as the one having issues

Copy BatchParser.dll from that instance...

You can do it either way. If you double click on it, after execution the command prompt window will close (unless there is a PAUSE command in the batch file)....

You may use the @sensitivity parameter. Please refer this for more information.

You can VERIFY it after the backup has completed. Below is an example.

FETCH NEXT FROM @cursor INTO @dbname

WHILE @@FETCH_STATUS = 0

BEGIN

SET @query = 'BACKUP DATABASE '+ @dbname...

Also what does the SQL Server Error log has?

T-SQL alternative to what Steve had mentioned. Execute

sp_readerrorlog 1

The last entry in the output would give you the time when the instance was restarted

If you don't find anything in the ErrorLog, try starting the instance from the command line using sqlservr.exe

This should give you some indication as to why the instance is not...