CAUSE
This behavior may occur after you install a program that overwrites
either of the following two Windows system files with an incorrect or
previous version:

Msvcirt.dll
Msvcrt.dll

This behavior may also occur if one of these two files is damaged or
missing.

RESOLUTION

To resolve this issue, replace these files with new copies from your
Windows installation CD-ROM. To do this, use the method for your
operating system.

Windows Millennium Edition
Click Start, and then click Run.
In the Open box, type Msconfig, and then click OK.
In System Configuration Utility, on the General tab, click Extract
File.
In the Specify the system file you would like to restore box, type
Msvcrt.dll, and then click Start.
In the Restore from box, browse to the location of your Windows
Millennium Edition (Me) CD.

NOTE: If you have an original equipment manufacturer (OEM)
installation of Windows Me, the Windows installation files may be
stored in the following location:
C:\WINDOWS\OPTIONS\INSTALL

In the Save file in box, type C:\, and then click OK. You receive the
following message:
Extract File

The destination folder
c:\
does not exist. Do you want to create it?

Click Yes, and then click OK.
Repeat steps 3 through 6, but substitute Msvcirt.dll for Msvcrt.dll.
Insert your Windows Me Startup disk, restart the computer, and then
select Minimal Boot on the Microsoft Windows Millennium Startup Menu
that appears.
At the command prompt, type Rename C:\Windows\System\Msvcrt.dll
Msvcrt.old, and then press ENTER.
Type Rename C:\Windows\System\Msvcirt.dll Msvcirt.old, and then press
ENTER.
Type Copy C:\Msvcrt.dll C:\Windows\System, and then press ENTER.
Type Copy C:\Msvcirt.dll C:\Windows\System, and then press ENTER.
Remove the Windows Me Startup disk, and then restart the computer.
Windows 98
Click Start, and then click Run.
In the Open box, type SFC, and then click OK.
In the System File Checker dialog box that appears, click Extract one
file from installation disk.
In the Specify the system file you would like to restore box, type
Msvcrt.dll, and then click Start.
In the Restore from box, browse to your Windows 98 installation CD.

NOTE: If you have an original equipment manufacturer (OEM)
installation of Windows 98, the Windows installation files may be
stored in the following location:
C:\WINDOWS\OPTIONS\CABS

In the Save file in box, type C:\, and then click OK. You receive the
following message:
Extract File

The file has been successfully extracted.

Click OK.
Repeat steps 3 through 6 but substitute Msvcirt.dll for Msvcrt.dll.
Quit System File Checker, and then restart the computer in MS-DOS
mode.
At the command prompt, type Rename C:\Windows\System\Msvcrt.dll
Msvcrt.old, and then press ENTER.
Type Rename C:\Windows\System\Msvcirt.dll Msvcirt.old, and then press
ENTER.
Type Copy C:\Msvcrt.dll C:\Windows\System, and then press ENTER.
Type Copy C:\Msvcirt.dll C:\Windows\System, and then press ENTER.
Restart the computer.

Bill Starbuck (MVP)