Introduction
Under Windows 2000 and XP, our utilities don't use the Aspi layer any more. We wrote a specific service, named Lsdiorw, running under the local system account, which calls SPTI and IOCTL functions and allows plain users to access the physical drives, even without administrator rights.

Installation and Desinstallation
When running MacDisk installer (demo/trial version or full version), a special installer for the Lsdiorw service, named instserv.exe is launched (which installs and starts the service). This installer should run from an administrator account.
If the installation process fails and you can't find the files lsdiorw.exe and instserv.exe on your computer (normally in the folder C:\Program Files\LS_Duhem\lsdiorw), you can download a fresh version from our Web site. The archive contains the three files (the service Lsdiorw.exe, the installer instserv.exe and the uninstaller uninstserv.exe).

• Version 1, to be used with MacDisk version 6.2 and lower.
• Version 2, to be used with MacDisk version 6.5 and higher.
• Version 4, to be used with MacDisk version 7 and higher, and with CD-XRay and Disk-XRay version 2 and higher.

When desinstalling MacDisk, the service is desinstalled by the uninstserv.exe utility. If you get a message about some items which could not be deleted, it means that the service could not be deleted directly. It will be deleted when you reboot your computer. You will then be able to delete manually the remaining folders.

GUI Installer/Uninstaller
Since the command line versions are fine in an automatic installation process but not very helpful when the user tries to do it under Windows, the Lsdiorw folder, from version 7, also contains an utility named ledinst.exe which offers a graphical interface and two buttons Intall and Uninstall (one being greyed out).

How to Know Which Version is Running?
In the Lsdiorw folder, leave the cursor on the executable (lsdiorw.exe). Windows should display its version.
You can also use the Service console (go to Start, Parameters, Control Panel, Administrative Tools, then Services). When you select the line with Lsdiorw, it displays its version from version 4. If it doesn't, this should be version 2.

Working Mode
When idle, the service runs in the background and does nothing. In particular, it doesn't consume resources. It runs under all accounts (even for a plain user).
When a program wants to access its functions, its passes the addresses of memory regions which will be shared amongst them to transfer commands and data.
When the application exits, it asks the service to free the handles opened on those memory regions and to return to the idle state.

Errors
In case of error, the Service Manager can stop the service Lsdiorw. You then have to restart it. Go to Start, Parameters, Control Panel, Administrative Tools and Services. In this so-called console, right click on the Lsdiorw entry and select the Start item. This operation should be done from an administrator account.
Please note that, in this case, you don't have to reinstall the service from scratch. Services can be correctly installed but not yet started.

Error on Upgraded Version
It can also happen that the service fails to do its work when a version 7 is installed on a former version using the Aspi layer. The solution is to open the Registry key HKEY_LOCAL_MACHINE, Software, LS_Duhem, MacDisk, Aspi and to write the string '-1' (minus one, without the quotes) to replace the version string of the Aspi layer.

Disk Access Rights
Administrators may legitimately fear that users could do some low-level operations (like formatting) on some disks that should be protected against that. To implement the security model, administrators may define, in MacDisk, a black list of disks.
This black list contains all local disks on the computer that should not show in the Drive Selection window.
Since the black list is a normal feature of MacDisk, we implemented a method to lock it (the normal user can't access it any more). See the file "admin.txt" in the installation folder.
On the other hand, MacDisk version 7 and higher doesn't display hard disks formatted as FAT, FAT32 or NTFS by default, to protect the user against themselves.

Setting of Windows Firewall (XP SP 2 and higher)
If your computer runs under Windows XP SP2 and higher and if you are using Windows Firewall, you have to correct its settings to allow MacDisk to call its low-level disk access service Lsdiorw.exe.
To this end, open the Firewall in the Control Panel (to be found in the Start menu or in the Start menu, then the Settings folder). On the Exceptions tab, click Add Program. If the service Lsdiorw appears in this list, double click on its name. If it not the case, click the Browse button. The service Lsdiorw is to be found in the folder C:\Program Files\LS_Duhem\Lsdiorw. It will appear with its .exe extension or not, depending on the settings you use to display files and programs in the Explorer.