Article ID: 96519 - View products that this article applies to.
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Microsoft DEFRAG operates on the MS-DOS logical drive level only. Third-party partitioning utilities that modify or translate disk geometry (such as Disk Manager and SpeedStor) operate beneath the MS-DOS file system and are therefore transparent to DEFRAG.
DEFRAG cannot share access to a drive with other tasks; therefore, you cannot run DEFRAG if Windows or DESQview is running.
DEFRAG does not work in the following situations:
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Situation Reason ---------- ------ Network Drive Network software usually does not allow full single-tasking access to the entire drive, including the file tables. Often network drives (such as Novell NetWare) use another file system. CHKDSK Errors Errors in the drive organization can cause unpredictable results from DEFRAG. DEFRAG identifies most CHKDSK errors while reading the drive organization, and then refuses to run until you correct them. Windows DEFRAG cannot operate properly in a multitasking or task-switching situation; therefore, it detects Windows in real, standard, and 386 enhanced modes and does not run. Task Swapper DEFRAG cannot operate properly in a task-switching situation; therefore, it detects the MS-DOS Shell task swapper and does not run. Interlnk Drives Interlnk is not designed to support defragmentation and other low-level utilities. Specifically, it does not implement interrupts 25 and 26. Fastopen The Fastopen program tracks which files are located in which clusters on your disk. DEFRAG rearranges data on a cluster level, which confuses Fastopen. JOIN JOIN does not allow normal access to a drive. SUBST SUBST drives do not have their own file tables or directories to optimize.