SUMMARY

When the Microsoft MS-DOS version 5.0 installation program is run on a machine that had a previous system present, the program copies the CONFIG.SYS and AUTOEXEC.BAT files to CONFIG.OLD and AUTOEXEC.OLD, replacing them with new ones of its own. The Microsoft MS-DOS 5 Upgrade's Setup, however, simply modifies the current files. This can cause problems because the MS-DOS installation program changes system settings such as the "files=" and "buffers=" settings to values that may cause programs already installed on the machine to fail.

One situation in which this is a problem is if Windows is present on the system. The installation program sets "files=" to 10, a value that is too low for Windows to run.