Skip to content Skip to main navigation Skip to footer

How to Manually Specify CHS

There are some circumstances where your system configuration may require you to manually specify cylinder/head/sector (CHS) values for a drive attached to your system.  Image for DOS and Image for Windows provide a number of ways to accomplish this.

Please note that you may obtain the appropriate CHS values by running the PartInfo utility.

Image for DOS and Image for Windows - Command Line Restore

When restoring from the command line, the C=xH=xS=x parameters may be used.  The C= value specifies the last cylinder, H= specifies the last head, and S= specifies the sector count.  Please refer to the following example:

image.exe /R0VC=900H=31S=63 d:\system~1\monthl~1

In the above example, hard drive 0 was specified as the target, the last cyclinder is 900, the last head is 31, and the sector count is 63.  Each parameter is optional, and their order does not matter.

Image for Windows - Interactive Restore

You may create a text file named IFW.INI, and create a section header of the format [HDx], where x is the target hard drive number (zero based).  The parameters and values to be specified here are the same as shown above for command line use.  Here is an example of IFW.INI content:


This specifies the first hard drive (HD0), a last cylinder of 800, a last head of 31, and a sector count of 55.

You may also specify a MBRCHS=n setting, where n may be either 0 or 1.  If MBRCHS=1 is used, Image for Windows will attempt to obtain the appropriate CHS values from existing partitions present in the MBR.  For example:


If MBRCHS=0 is used, or if the MBRCHS=n setting is omitted, Image for Windows will fall back on the C=, H=, and S= values supplied, if any.  If no such values are provided in this case, Image for Windows reverts to its default behavior of obtaining the CHS values from Windows itself.

Was This Article Helpful?