DOSBox FAQ

Performance

Q. My game runs fine at first then an error message pops up on dosbox saying that the video file format is wrong. How or what can I do to fix this, if there is anything known?

Q. My game/application runs slowly, how do I improve speed?

A. Increase cycles. Use core=dynamic. Try different output modes (e.g. output=overlay). Increase Frameskip. Disable unneeded components in the dosbox.conf such as Sound, mouse or joystick emulation. A nice speedup can be achieved by using a different compiler than GCC. If all else fails, find a faster computer to run DOSBox on. Also be sure to check the compatibility section of this FAQ as some game/applications are more trouble (or resource hogs) than others.

Q. The Sound/Music for my DOS game/application sounds terrible what can I do?

A. This is a complicated issue covered in the Sound section of the wiki. It's important to remember to install or setup game/applications correctly to use the correct sound devices (INSTALL.EXE, SOUNDSET.EXE and SETUP.EXE are popular program names to look for). The capabilities of the hardware as well as the preferences of the programmer vary: Therefore what may sound "best" on one particular game may not be the "best" for another. Sometimes changes need to be made to the dosbox.conf file (or a new conf file) to get the best results. Also, game sound/music may have an impact on the speed at which the game/application runs and running DOSBox with limited resources may result in incomplete or 'choppy' sound being heard. (see previous question)

Q.How do I change the memory size so that I can run programs that require more than the default settings (eg. Windows 1.01 or some other demanding OS)?

A.See the memsize option detailed in Configuration:DOSBox.

Usage

Utilisation en français:la dosbox est le plus souvent utilisée en anglais. Quand vous avez un clavier AZERTY si vous ne le chargez pas d'abord, les commandes que vous tapez ne correspondront pas aux touches tapées. Pour remédier à celà, tapez d'abord:

keyb fr

et le clavier AZERTY sera chargé. (et non plus le QWERTY) (keyb fr veut dire: keyboard french)

Q. Using Mac OS X 10.5.3 without a problem (MOO) and when upgraded to 10.5.4 MOO started flashing rainbow colors instead of the normal background in full screen mode (works fine in windowed mode.) I have a warning about the quickdraw capability being deprecated in my console window. Any suggestions?

A. Apple updated the video drivers for certain NVidia cards in 10.5.4. This update also disabled 256 color mode support resulting in many graphical errors in programs that run in that mode. The only known solution is to downgrade your video drivers to the pre-10.5.4 release. Instructions for doing so are available in this thread: http://forums.macrumors.com/showthread.php?t=490676 . Alternatively an installer package has been made to automate the process; this package is available from: http://70.181.80.166:82/blog/archives/2008/07/mac-os-10531054-nvidia-256-colors.html

Q. My backslash key is mapped to ']' with DOSBox on Windows. Is there a workaround?

A. This is usually a keyboard driver problem. You can either fix your driver or use the keymapper as a workaround. Here is a thread on VOGONS, detailing the problem:http://vogons.zetafleet.com/viewtopic.php?t=18465

- Driver fix on Windows XP

Right click My Computer, select Properties. On the Hardware tab, select Device Manager. Find your keyboard, right click, Update driver. Select No, not this time, then Install from a list or specific location (Advanced). Select Don't search. You arrive to a screen where compatible drivers are listed. Changing from Microsoft Natural PS/2 driver to PC/AT Enhanced PS/2 driver reportedly solved this issue. You can experiment with any other compatible device you find on the list. If you are using an USB keyboard try the keyboard manufacturer's drivers.

- Driver fix on Windows Vista

Click on the Windows button, right click on Computer, select Properties. Next, select Device Manager in the top left corner, and Continue on the User Account Control screen. Find your keyboard under Keyboards. Right click on the keyboard entry, select Update Driver Software.... Then select Browse my computer..., and Let me pick.... Here you can change your current driver to another compatible one, or use the disk provided by your manufacturer.

- Workaround using DosBox Keymapper

Press CTRL-F1 to enter the keymapper and select the backslash with your mouse. Press the DELETE button that will show up on your screen. Then press ADD to bind backslash to another key. Simply press an unused key to bind it to this. Press SAVE and then EXIT to return to the main screen.

Q. My cursor is trapped within the DOSBox window when I click inside. How do I get the cursor out?

A. DOSBox will capture your mouse when you click inside the display window (and you have autolock=true set in the Dosbox.conf). Simply press CTRL-F10 to release the mouse.

Q. I have set Gnome to load DOSBox when I click on .COM files. How do I script it to exit DOSBox when I quit from the game?

A. with -exit as commandline parameter for DOSBox.

Q. How do I access my hard drive/cdrom in DOSBox?

A. See the information on the MOUNT command, or type intro mount or intro cdrom in DOSBox for the basics.

Q. I have an ISO image I made of files for backup purposes. How do I access it in DOSBox?

A. See the information on the IMGMOUNT command

Q. How do I unmount or change images? I need to swap CD images in the drive.

A. You may assign more than one image file to IMGMOUNT, to swap images use CTRL-F4. You can also unmount images by using the -u switch. See IMGMOUNT for more information.

Q. I have created an image from a CD that includes CD audio tracks, when I access it in DOSBox only the first (data) track is available.

A. Be sure to use the bin/cue format for mixed mode CDs (CDs with a data and audio tracks) and always pass the cue file to IMGMOUNT.

Q. When I write : it turns out > or when i write å ä ö or any other non standard us character. How can I fix this for my keyboard?

A. Use the KEYB command to change your Keyboard layout.

Q. I can't find the ":" symbol anywhere in my dosbox. I am using Vista on a laptop. Please advice me how to fix the problem.

A. Use the left shift instead of the right shift. A number of keys are affected by this problem. For a workaround for other keys like "\", see the second answer.

Q. How do you/I scroll up to see text that is not visible in the DOSBox window? Certain apps will print a long string of text, and you can't see it all.

A Unlike the DOS window in Windows 2000, XP and Vista, DOSBox exactly emulates a full screen DOS session. Hence it doesn't support scrolling up and down. However, MS-DOS included a program to allow you to 'press any key' to scroll down called MORE.COM. This is how to do it on Windows:

1. Try and find a copy of MORE.COM from MS-DOS 5.0 (good luck)
2. Put it in C:\C
3. Edit C:\Program Files\Dosbox\dosbox.conf in Notepad
4. Go to the bottom of the file, where it reads [autoexec]. Add to it or change it to read:
   [autoexec]
   MOUNT C C:\C
   PATH=%PATH%;C:\
   
   
5. Save it, close DOSBox and then re-open DOSbox.
6. Now, say you wanted to use this command:
   C:\> type readme.txt
   
   Instead type this:
   C:\> type readme.txt | more