SWAPFILE.EXE May Not Recognize Logical Drives in Windows

• Microsoft Windows operating system versions 3.0, 3.0a, 3.1, 3.11

SUMMARY

The Swapfile program included with Microsoft Windows may not recognize disk drives with drive letters greater than C if disk partitioning methods other than FDISK have been used, such as Disk Manager (DMDRVR.BIN), SpeedStor (SSTOR.SYS), EDRVR.SYS, and so on. The Swapfile menu's Next Drive command is unavailable (dimmed) if no drive other than drive C is recognized by Swapfile.

The Swapfile program allows you to create a swap file on a particular partition if that partition contain 512 byte sectors. A nonstandard hard drive may have a drive C that is standard (512 byte sectors), but all drives after C (D and greater) are nonstandard (sector size other than 512).

It is possible for a temporary swap file to exist on logical drives such as drive D or E if Windows is installed on one of those drives.

MORE INFORMATION

The Swapfile program's 512 bytes per sector requirement is inherited from the BIOS of the personal computer. Third-party partitioning utilities (such as Ontrack's Disk Manager and Storage Dimensions' SpeedStor) circumvent this limitation by translating all communication between the disk and the BIOS. To ensure compatibility with the industry standard of 512 bytes per sector, SWAPFILE.EXE was written to not support any type of disk translation.

NOTE: If you use OEM versions of the FDISK command earlier than version 4.01, which allow partitions greater than 32 MB, you encounter this problem. These OEM versions of MS-DOS include Wyse DOS 3.21, NEC DOS 3.31, and Zenith DOS 3.3 Plus.

If the drive has been partitioned using a third-party partitioning method, do not use the Swapfile program. Corruption of the file allocation table (FAT) can occur, resulting in data loss. Using FDISK is the recommended partitioning method when you plan to use Windows utilities.

REFERENCES

"Microsoft Windows User's Guide," pages 520-531