DOCUMENT:Q149228 09-AUG-2001 [winnt] TITLE :How to Disable Mouse Acceleration PRODUCT :Microsoft Windows NT PROD/VER:3.1 3.5 3.51 OPER/SYS: KEYWORDS:kbusage ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 3.1 - Microsoft Windows NT Workstation version 3.1 - Microsoft Windows NT Advanced Server, version 3.1 - Microsoft Windows NT Workstation versions 3.5, 3.51 - Microsoft Windows NT Server versions 3.5, 3.51 ------------------------------------------------------------------------------- SUMMARY ======= The default settings for the mouse have acceleration enabled. To disable acceleration in the Mouse Control Panel tool, you can move the Mouse Speed slide bar all the way to the left. However, this makes the mouse pointer move very slowly in relation to the movement of the mouse. Disabling acceleration is desirable for some users of Windows NT, such as CAD users, but making the default mouse speed the only speed is impractical. MORE INFORMATION ================ To calculate the mouse speed under Windows NT, three settings are used: Mouse Speed, MouseThreshold1, and MouseThreshold2. Mouse Speed sets the relationship between mouse and cursor movement when the value of either MouseThreshold1 or MouseThreshold2 is exceeded. When this occurs, cursor movement accelerates according to the value of MouseSpeed. MouseThreshold1 and MouseThreshold2 set the maximum number of pixels the mouse can move between mouse interrupts before the system alters the relationship between mouse and cursor movement. If the mouse movement exceeds the threshold defined by MouseThreshold1 and if MouseSpeed is greater than 0, the system moves the cursor at twice the normal speed. If the mouse movement exceeds the threshold defined by MouseThreshold2 and if MouseSpeed is 2, the system moves the cursor at four times the normal speed. Using the slide bar in the Mouse Control Panel tool, you cannot disable acceleration without making the mouse pointer respond very slowly to the mouse movements. It is possible to overcome this limitation by manually setting the MouseThreshold settings so low that any movement at all is accelerated. Mouse pointer speed will no longer increase factorially with an increase in mouse movement, but still moves at a rate higher than normal. WARNING: Using Registry Editor incorrectly can cause serious, system- wide problems that may require you to reinstall Windows NT to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk. To implement a higher default mouse pointer speed for the currently logged in user, use the Registry Editor (Regedt32.exe) to edit the following registry key: HKEY_CURRENT_USER\Control Panel\Mouse 1. Set the value of MouseThreshold1 to 0. 2. Set the value of MouseThreshold2 to 0. 3. Set the value of MouseSpeed to 1 or 2 (1 doubles the normal speed, 2 quadruples the normal speed). 4. Close Registry Editor, close all applications, and restart Windows NT. Additional query words: prodnt mice ====================================================================== Keywords : kbusage Technology : kbWinNTsearch kbWinNTWsearch kbWinNT351search kbWinNT350search kbWinNTW350 kbWinNTW350search kbWinNTW351search kbWinNTW351 kbWinNTW310 kbWinNTSsearch kbWinNTS351 kbWinNTS350 kbWinNTS310 kbWinNTAdvSerSearch kbWinNTAdvServ310 kbWinNTS351search kbWinNTS350search kbWinNTS310search kbWinNT310Search kbWinNTW310Search Version : 3.1 3.5 3.51 ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.