Friday, December 9, 2011

Administrator cannot change, delete or take ownership of file

Problem: It is well known that if a file is locked in Windows, an administrator can take control of the file by taking ownership of it, give himself permissions to write/delete it and then perform pretty much anything he needs to do with the file. Sometimes, however, you just receive an error message when you try to take ownership, even though you are an administrator, and even though the command prompt or Windows Explorer you are working from has been started by right-click - "Run as administrator"

Solution: Open Computer Management and open shared folders - open files. If the file in question is being held by someone that has opened the file over a fileshare, you first have to terminate their connection to the file before you can manipulate it. Of course, you should first make sure you are not disturbing any work they are doing on the file.

Tuesday, October 4, 2011

Cannot connect to any computer except DC

Problem: The only network traffic (ping etc.) that could pass in a Win7/Server 2008 R2 domain was from each client computer to the domain controller. No client computer could contact each other. Even the domain controller could not initiate contact towards a client computer.

Reason: In the Server 2008 R2 active directory domain organizational unit (OU), a Group Policy Object (GPO) had been created to disable the local client's firewall and allow any network traffic (which was ok from a security point of view, since the network was completely disconnected from anything outside). When applied, the firewall was indeed not started, but somehow the idea backfired by blocking all but those client computer connections made to the DC.

Solution: The Firewall service was reenabled in the GPO:
Policies-Windows Settings-Security Settings-System Services-Windows Firewall-Startup type=Automatic
Instead the Firewall setting was set to off for the domain profile (which is the active profile for computers within a domain):
Policies-Windows Settings-Security Settings-Windows Firewall with Advanced Security-Domain Profile Settings-Firewall state = off

It seems absolutely illogical to me that switching off the firewall service would block most network traffic. Maybe some special case in my domain caused it - nevertheless, there was no doubt that my changes were the solution to my problem - even proven by the fact that reversing them would lead to reintroducing the problem.

Saturday, September 10, 2011

PHP scripts stopped working when moved

Problem: After having moved some PHP scripts from one web server to another, they stopped working , or only worked partially. One of the webpages showed all the HTML and the upper part of PHP generated code, but strangely after a certain point the rest of the PHP code had just been ignored.

Solution: I loaded one of the script files in the open source DevPHP editor and chose Format on the menu. The Mac (CR) option was checked. I changed it to Windows (CRLF), uploaded the file again and reran it. Voilla, it worked!

Obviously, some PHP parsers may be more picky than others with how they read line breaks.

Monday, September 5, 2011

ODBC 32 vs. 64 bit

Scenario: I needed to connect 32 bit software running on a 64 bit Windows 7 OS to an SQL server via ODBC. Using a User DSN, everything was fine - setting up a System DSN instead, the application could no longer find it or and connect to the database. I preferred setting up a System DSN, so that any user logged on to the computer would be able to run the software without further hassle in setting up the needed ODBC connection.
Cause: An ODBC System DSN in 32 and 64 bit versions are two separate matters, hence a 32-bit application will not see a 64 bit ODBC System DSN and vice versa. User DSNs are however visible on both sides. Confusing.
Gotcha: Both the 64 and 32 bit version of the ODBC tool's is named odbcad32.exe. Hence, the Win7 standard method of writing this in the search field at the bottom of the start menu would always give you the 64 bit version. You have to run %windir%\syswow64\odbcad32.exe (for instance via the run dialog, keyboard shortcut winkey-r) to start the 32 bit ODBC application.
Reference: Microsoft's Knowledge Base article 942976

Tuesday, August 16, 2011

Cannot logon to newly installed SQL Server

Problem: After a fresh install of SQL Server 2008 R2 on a Windows 7 computer, where Windows user group BUILTIN\Administrators were given administrative rights, I was not able to log on to the database from Microsoft SQL Server Management Studio while logged on to Windows as a user who was a member of the Administrators group and thus should have been granted access. The error received was: Login failed for user 'COMPUTERNAME\user'. (Microsoft SQL Server, Error: 18456).

Solution: Turn off User Account Control, or if you prefer to leave it on, make sure you start SQL Server Management Studio as an administrator (right-click the icon and select Run as administrator).

Tuesday, May 24, 2011

Edit and display local characters in .bat scripts

Problem: Sometimes I need to write a batch script echoing instructions in my native language Norwegian, including its special characters æ, ø and å. The only thing is, if you edit the .bat or .cmd file in Notepad, it will translate into garbled characters because of an character encoding issue.

Solution: With my favorite plain text editor, the free Notepad++, I have the possibility of selecting encoding for the file I am editing. Menu item Encoding-Character sets-Western European-OEM 850 works well for the Norwegian special characters, and possibly others.

Wednesday, March 23, 2011

OpenVPN service dependency service failed to start (Error 1068)

Problem: I wanted to start OpenVPN as a service so that I could use a Windows Server 2003 as a router for an OpenVPN connection. The service would not start even though I set it to start automatically from the Services app in Administrative Tools, claiming error 1068: The dependency service or group failed to start.

There's a lot of people complaining about this error out there, but I could not find a better answer around than reinstalling the OpenVPN software. I am not a big fan of reinstalling without getting to the bottom of the problem - it means you haven't learned anything useful for the next time you encounter the problem.

Investigation: In the process of setting up OpenVPN, I had installed a previous version of it some time ago, and then reinstalled at a later time to get the latest version. By examining the system event log, I discovered that together with an error message (event 7001) for an unsuccessful start of the OpenVPN service, there was also an event ID 7000 stating that "The TAP-Win32 Adapter V8 service failed to start". Funny, since my TAP virtual adapter that came with the (latest) OpenVPN installation was marked V9, not v8. That nailed it:

Solution: The OpenVPN service referenced an older version of the TAP virtual adapter than the one now installed. I changed the following registry value:


...from "TAP0801" to "TAP0901", rebooted and the OpenVPN service had already connected by the time I was logged in.

Monday, February 28, 2011

VS2010 crashes when editing

Problem: VS2010 crashes the instance you enter a character or paste text into a source file. The message displayed (sometimes - other times VS2010 simply dies and disappears without further notice) is:

Visual Studio has encountered an exception. This may be caused by an extension. You can get more information by running the application together with the /log parameter on the command line, and then examining the file 'C:\Users\USERNAME\AppData\Roaming\Microsoft\VisualStudio\10.0\ActivityLog.xml'

Solution: The solution was found in this forum, which states:
It appears to be due to missing registry information. Adding the default value to the below registry key solved the problem.
On 32-Bit Windows: [HKEY_CLASSES_ROOT\CLSID\{73B7DC00-F498-4ABD-AB79-D07AFD52F395}\InProcServer32]
On 64-Bit Windows: [HKEY_CLASSES_ROOT\Wow6432Node\CLSID\{73B7DC00-F498-4ABD-AB79-D07AFD52F395}\InProcServer32]
The "(Default)" value should be one of the following:On 32-Bit Windows: "C:\Program Files\Common Files\Microsoft Shared\MSEnv\TextMgrP.dll"
On 64-Bit Windows: "C:\Program Files (x86)\Common Files\Microsoft Shared\MSEnv\TextMgrP.dll"

Tuesday, February 22, 2011

Win7: Restore .bat default behaviour

One of those small, very annying problems: I had managed to assign .bat files to open with my favourite cleartext editor (Notepad++ by the way), so that instead of running the bat file upon double-click, it opened in the editor. Now I wanted it reverted back to the original behavior.

I finally came up with a working solution: Just delete this registry key with all subkeys and life as you knew it before will be smiling to you again: