Mplay32.exe Leaks Memory When Playing a MIDI File

This article was previously published under Q223774
This article has been archived. It is offered "as is" and will no longer be updated.
When you play MIDI files with the Microsoft Windows Media Player (Mplay32.exe) and specify Auto Repeat and Rewind, a memory leak of 4 KB occurs for each play. A memory leak does not occur when playing wave files on Media Player.
This problem occurs because the pointer, which maintains memory addresses that saved 4 KB at the time the heap was allocated, performs heap allocation without releasing the heap and overwrites the pointer value.
To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to:
For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:
Microsoft has confirmed that this is a problem in Windows NT 4.0. This problem was first corrected in Windows NT version 4.0 Service Pack 5.

Article ID: 223774 - Last Review: 11/02/2013 23:58:00 - Revision: 3.0

  • Microsoft Windows NT Server 4.0 Standard Edition
  • Microsoft Windows NT Workstation 4.0 Developer Edition
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