Setting up Basilisk II for Windows

(updated January 31, 2025)

(You can also set up Basilisk II for OSX/macOS or Basilisk II for Linux)

Basilisk II emulates up to a 68040 Macintosh. You can install Mac OS 7.1 to Mac OS 8.1 in the emulated machine.
This guide begins by describing how to get started with MacOS from a real CD Rom or CD Rom image file, which is the faster and easier way to get started. Scroll down to OPTION TWO for instructions on how to install from floppy disk images.

You need:

• Basilisk II itself.
• A valid ROM file. You can get this from your old Macintosh computer as described here, or you can find one online.
• A real CD Rom or a CD Rom image file of the Mac OS you want to install. (Mac OS 7 or 8).

Tip: To install from a set of floppy disk images, see further below at OPTION TWO.

Note: If you are using a CD image, you may need to right-click the image (in Windows), and set it to “read only” in the “properties” menu. This will solve the “The system software on the startup disk only functions if on the original media, not if copied to another drive” error message when attempting to boot from the image.

Tip: We do not offer or link to ROM files, but you can search for the “redundant robot sheepshaver” tutorial site and download the performa rom.

• Insert your CD-ROM. Run “BasiliskIIGUI.exe.” On the “Volumes” tab, at “CD-ROM Drive” open the list and select the correct CD-Rom drive letter. Then click Add.

Figure 1: BasiliskII GUI with CD drive added.

• Go to Volumes tab below.

• Run “BasiliskIIGUI.exe”.
• Drag your CD Rom disk image into to the volumes list.

Figure2: BasiliskII GUI with CD Rom image dragged into the volumes list.

• Go to Volumes tab below.

• Click “Create” to create a hard disk image file onto which to install Mac OS.
  

The window Create Volume File appears.

• Navigate to a suitable location where to save the hard disk image file.
• At Size (MB) enter 2000 (see note).
• Name the image file under “Selection”:

Figure 3: Create Volume File set to create a 2000Mb image file named MacOS8.1.img in the folder C:\mac-hd.

Note: The maximum size of hard disk images that boot reliably is 2 GB. If you need more space, you can create additional larger hard disk images.
Tip: Mac OS requires at least 220 MB for a typical install.

• Click OK.

The GUI returns to the “Volumes” tab and the hard disk image file will be listed as added to your emulated Mac.
Tip: With your mouse, you can drag the entries in the volumes list to a different position.

• Set “Boot from” to “CD Rom”.

• Make sure the first entry in the volumes list is your CD Rom image file.

Disable CD-ROM Driver: disables CD access.
Try to automatically detect new removable media (enable polling): when checked, BasiliskII periodically checks for a newly inserted real CD.
Enable “My Computer” icon on your Mac desktop (external file system): when checked, BasiliskII gives access to one or more host drives.
Mount drives: lets you select the host drives that will be available through the This PC icon on the desktop.

Tip: See below at “Sharing a single folder instead of a whole drive” for more fine grained access to a specific folder)

Do not attempt to start BasiliskII just yet, follow the rest of the guide to configure BasiliskII

• Switch to the “Graphics/Sound” tab.

• Select you video Type: Window or Full screen.

You can select whether BasiliskII starts in Full screen or in a Window.
Tip: You can switch between Full screen and Windowed modes by using the Ctrl-Enter key combination.

• Select a Window Refresh Rate.

The window refresh rate determines the number of times per second the screen is refreshed. Choose Dynamic for best performance.

• Select a Window width and height.

Note: The selected width and height determine the size of the BasiliskII window AND the resolutions from which you can choose in Mac OS.
Tip: you can manually enter other values than the predetermined ones available in the drop boxes.

Figure 4: Graphics and sound settings.

Other settings on the Graphics/Sound tab

• Render driver
• Vertical Sync
• Disable Sound Output

• Switch to the “Keyboard/Mouse” tab.

• Use Raw Keycodes

Note: You must use a keycodes file (included in our download) to support other keyboard layouts and languages besides English. Select Use Raw Keycodes and then browse to an appropriate keycode file. We provide an iso and ansi version.

• Reserve Windows Key

You can use the “Reserve Windows Key” option to prevent opening the Windows menu when using the Windows key in certain key combinations in Mac OS.
Note: Not all key combinations for which the Windows key is needed can be reserved. Among others, Windows key+L, Windows key+G cannot be prevented.

• Mouse Wheel Function

You can control the mouse wheel behavior: set it to either move the cursor up/down or pages up/down. The “Lines to scroll” option controls how many lines the cursor moves up/down with one mouse wheel roll.

Figure 5: Keyboard and Mouse settings.

• Skip the Serial tab and go to the Network tab

Figure 6: The serial port settings.

• Ethernet interface

Select which Ethernet interface to use. When you select “Basilisk II Slirp” you get default internet access.
Tip: For more advanced networking support (including running Appletalk) see below at Internet access/Networking.

Figure 7: the network settings

• Mac OS Ram Size (MB)

Set a suitable/realistic amount of memory available to Mac OS.

• Mac Model ID

When installing Mac OS 8, set the Mac Model ID to “Quadra 900 (MacOS 8.x)”.
When installing Mac OS 7, set the Mac Model ID to “Mac IIci (MacOS 7.x)”.

• CPU Type

You can select various CPU types with or without FPU. Set it to 68040 to install Mac OS 8.x

• ROM FILE

When preparing to use BasiliskII, you downloaded a rom file. Use the Browse button at “ROM File” to browse to and select your rom file.

• Don't use CPU When Idle

This option makes Basilisk use less system resources when idling.

• Ignore Illegal Memory Accessess

To ensure maximum stability always check “Ignore Illegal Memory Accessess”.

Figure 8: The memory and some miscellaneous settings

• Switch to “JIT Compiler”

• Enable JIT Compiler

The JIT (Just-In-Time) Compiler can greatly improve emulation speed. On modern host systems this not needed to achieve good speed.
Tip: Keep the JIT compiler disabled, as it also increases instability.

Figure 9: The JIT Compiler settings

This completes configuring BasiliskII. You are now ready to install Mac OS.

In the GUI, click “Start” to launch BasiliskII. The system starts up from the CD Rom or CD Rom image.

You will be asked to initialize the hard disk image you made. Give it a name and select “initialize.” See figure two, below.

Figure 10: Initialize the Drive

On the CD Rom find the program to install Mac OS. Run that to start the installation. Follow the instructions on screen. I suggest that you install the default software. You probably don't need to customize the installation right now. If you need something else from the CD, you can install it later. Hit “Quit” when the installation is finished.

Note: If you followed the above instructions but get an image of a floppy disk with a question mark, your CD Rom image might not be bootable. Try another one.

Figure 11: The Install Screen

When the installation is finished shut down Mac OS (special –> shutdown). To boot from the hard disk image, run “BasiliskIIGUI.exe” and remove the CD Rom image from the volumes list or drag the CD Rom image to the second position in the list. If you have been using a real CD Rom set the “Boot from” option to “Any”. Start the emulator.

Upon first run from the hard disk image, the MacOS Setup Assistant will run. You can configure the given settings, but the emulator will freeze if you attempt to configure network settings (unless you already configured the network option to use a Tap device). Shut down the assistant at that point.

You are now finished setting up the emulator.

Tip: If you customized the installation you may get an error related to the “A/ROSE” extension. In that case, reboot while holding the “shift” key and manually delete that extension.

Figure 12: A Fresh Install of MacOS 8.1

We provide a floppy disk image boot Mac OS and a hard disk image with floppy disk images to install Mac OS 7.5.3

In addition to the Basilisk program and GUI, you need:

• A System 7 Boot Disk.

Which is zipped floppy disk image named System70_boot.dsk. Extract this to your Basilisk II directory before you begin.

• The System 7.5.3 software

Which is a zipped hard disk image named OS753InstallerParts.dsk that contains al the floppy disk images to install Mac OS 7.5.3. Extract this to your Basilisk II directory before you begin.

Run BasiliskIIGUI.exe.

Note: To configure BasiliksII to install Mac OS 7.5.3 from floppy disk images you can follow our guide above EXCEPT for the settings in the Volumes tab and the Memory/Misc tab.

In the “Volumes” tab:

• Drag the System 7 boot floppy disk image into the volumes list.
• Drag the hard disk image containing the System 7.5.3 installer parts into the volumes list.
• Click “Create…” and create a new hard disk image on which you will install System 7.

Tip: See Volumes Tab in the guide above on how to create a hard disk image.

After creating the hard disk image you see all three images mounted:
Figure 13: Three disk images mounted in the Basilisk II GUI

Switch to the “Memory/Misc” tab.

• MacOS RAM size (MB)

Select a suitable amount of memory.

• Mac Model ID

To boot the System 7 boot floppy disk, the Mac Model ID has to be set to “MacIIci (MacOS 7.x).“

• CPU Type

Set the CPU type at 68040

• ROM File

Click “browse” and select your ROM file.

Figure 14: The Memory/Misc settings for installing Mac OS 7.5.3

Click “Start” to run the emulator. You may get an error related to “the selected AppleTalk connection.” Ignore it.

You will be asked to initialize the disk you created earlier. Follow the instructions to “erase” the data and give it a name. I named mine “System753.”

After that, if your emulated Macintosh has booted successfully, it should look a bit like Figure 15, below.

Figure 15: The Macintosh desktop after booting the System 7 boot disk

• Open the disk OS753InstallerParts.
• Double click on “System 7.5.3 01of19.smi”
• Click Agree

To agree to the terms. Wait for the files to verify. This unpacks the 19 installer parts. A disk icon named “Sys7.5 V7.5.3 CD Inst” appears on the desktop (see Figure 16).

• Double click Sys7.5 V7.5.3 CD Inst.

In the folder that opens, there will be an icon named “Installer.”

• Double click Installer.
• Click “Continue” in the dialog box.

Follow the on-screen instructions in the Install System Software dialogue.

• Select the default “Easy Install”.
• Select the “destination disk”

Use the Switch disk option to select the disk which you named earlier.

• Click “Install.”
• Click “Quit” when the installation finishes

Figure 16: Proceed with an Easy Install

You have now installed System 7.5.3! To boot from hard disk image onto which you installed Mac OS 7.5.3:

• Shut down the emulated Mac (click “Special” and “Shutdown”).
• Run the Basilisk II GUI.
• Remove the System 7 boot floppy disk image.
• Remove the disk image containing the system 7 install parts.

This will leave only the disk that you installed the operating system on.

• Click “start” to run the emulator, now booting from your fresh install of System 7.5.3.

Tip: The System 7 installation files contain additional system software you might want to install at a later time, so you should retain that disk image for future use.
Tip: After booting from the hard disk image, the This PC option becomes available (if enabled). See the guide above how to configure that option.

Figure 4: System 7.5.3

You should install Stuffit Expander so that you can download and install applications in your emulators. Download this hard disk image containing the Stuffit Installation program. After downloading the disk, add it to the volumes list.

You may also want to update to System 7.5.5. The update process is very simple. You can get the update here. Download that file to Windows and drag it into your disk image via the “This PC” icon (sometimes called “My Computer”). Run the installer.

I've written a few other guides for Basilisk II. You might want to read about getting online, or about some good software for the emulated 68K Macintosh. Check out the articles page for other guides.

You can set some preferences by manually editing the BasiliskII_prefs file.
Note: some settings might be overwritten when using the GUI after you manually set them.

scale_nearest true/false   (setting this to true or false determines the clustering of pixels when using a magnification rate)
scale_integer true/false (setting this to true limits the magnification rate to an integer, i.e disregards the decimal value set at mag_rate)
mag_rate integer.decimal (setting mag_rate allow you to start the emulator using a magnification rate. Takes values such as 1.3, 2.0 etc.) 
yearsof integer (sets the system date to current year minus the number you set)
daysof integer (sets the system date to current day minus the number you set)

You should install Stuffit Expander so that you can download and install applications in your emulators. Download this hard disk image containing the Stuffit Installer. After downloading the disk, add it to the volumes list.

When you place a wav file called “startup.wav” in the Basilisk folder, it will be played at start-up.

If you are upgrading from an old version of Basilisk II, the best thing to do is to download all files into a new folder and make a fresh start (but you can still use your old disk image and ROM). Most dll (application extensions) files included are needed to run the GUI. The number of dll files may be a bit overwhelming, but the up-side is that it is no longer necessary to install the GTK development kit to run the GUI.

If you kept your Rom file and hard disk image(s) in the old Basilisk II folder, copy them into the new folder. If they are outside your old Basilisk II folder, leave them where they are now.

Next, run the GUI, point to the required Rom and disks in the new folder (or where you kept them outside of the old folder) and adjust the other GUI settings to match what you had before. You can then run Basilisk II.

If everything is OK, you can remove the old folder and its content. If you had the GTK development kit installed to run the old GUI, and it is not used for any other program you have installed, you can remove it too.

NOTE: Basilisk II builds from 22-09-2020 and beyond support reading and booting from real CDs in 64-bit Windows.
NOTE: Basilisk II supports networking over a TAP device in Windows.

For users of builds from before 22-09-2020: Both the cdenable.sys driver and the basilisk ethernet driver will not work in 64-bit Windows versions. Therefore you can't access cd-roms and can't make appletalk work on these windows versions. You can, however, make .iso images of your cd roms and add them to the volumes list in the BasiliskII GUI. For internet access you can use the “slirp” option. You can place the cdenable.sys driver in the \Windows\SysWOW64\drivers folder to get rid of the (faulty) error reported about not being able to find the driver in the \windows\system32\drivers folder. The currently available experimental 64-bit GTK package has not been tested with BasiliskII.

We're all done! For more help you should check out our Macintosh Emulation Forum. Big thanks to Gwenole Beauchesne for developing JIT Basilisk II. Additional thanks to Marc Hoffman for his work documenting Basilisk II more than 20 years ago.