This article was previously published under Q98345
Retired KB Content Disclaimer
This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
The MS-DOS 6.0 DoubleSpace disk-compression utility executes somefloating point (non-integer math) calculations and therefore mayattempt to use a math coprocessor (80x87 or equivalent) if one ispresent. If a machine's numeric processing system is substandard orcompromised due to the presence of device drivers, TSRs, or faultyhardware, DoubleSpace may either report inaccurate time estimates forcompletion or fail and generate the following errors:
Run-time error R6002 - floating-point support not loaded
Run-time error R6002 - floating-point error
Error: R6101 - Floating Point Divide by Zero
MS-DOS 6.2 DoubleSpace does some floating point arithmetic, but itdoes not attempt to use a math coprocessor even if one is present. This issue can occur in other programs that do not use the math coprocessor.
NOTE: In some cases, no runtime error(s) are displayed, andDoubleSpace stops responding (hangs) early in the compression process.
IMPORTANT: Since DoubleSpace has detected a potential problem withyour system, perform a full system backup or make sure you can fullyrestore the machine from removable media before you proceed with thesesteps.
Use the following steps to troubleshoot DoubleSpace R6002 errors:
Turn the machine off, then turn it on again. Press the F5 key when the "Starting MS-DOS" message appears to perform a "clean start." If your machine requires that a device driver is loaded in the CONFIG.SYS file to boot properly, press the F8 key to perform an "interactive start" and load ONLY the device driver(s) required. If the machine is rebooted at any point in the DoubleSpace process, be sure to use the EXACT same clean or interactive start each time. If DoubleSpace completes successfully, one or more of the device drivers or terminate-and-stay-resident (TSR) programs that were bypassed are probably causing the problem.
If DoubleSpace still fails with the R6002 error, try adding the following line to the CONFIG.SYS file using MS-DOS Editor or another ASCII text editor: set no87=nomath Restart your computer to make this change take effect. The SET NO87 environment variable instructs DBLSPACE.EXE not to use the math coprocessor for floating-point calculations. The SET statement should be placed in the CONFIG.SYS file, not the AUTOEXEC.BAT file. (If DBLSPACE.EXE is restarted, it may not process the AUTOEXEC.BAT file completely.) It doesn't matter what you set NO87 to as long as the NO87 variable is in the MS-DOS environment. For example, you could set NO87=NO or NO87=MICROSOFT, and DoubleSpace would not use the math coprocessor. To remove the NO87 environment variable, type "set no87=" (without the quotation marks) at the MS-DOS command prompt and then press ENTER.
If DoubleSpace continues to fail, the coprocessor itself, the coprocessor subsystem, or some other hardware component may be causing the problem.
In the case of 286, 386, and 486 SX machines, try removing the coprocessor for testing purposes. If the machine is a 486 DX, verify that the system's ROM BIOS is current and specifically designed for use with a 486 DX, not a 386 or 486 SX.
In rare cases, incorrect CMOS or system board DIP switch settings, faulty system RAM, or other hardware problems may cause R6002 errors. Contact your system vendor or manufacturer to verify the CMOS and DIP settings are correct. If the error persists, remove all system components not absolutely required to operate the machine (optional I/O adapters and so forth), use replacement parts (in the case of system RAM), or have the machine inspected by a hardware repair technician.
6.00 FPU NDP dblspace double space runtime stop hang clean start