#986 Increasing the Default DOS Environment Size

Problem: Attempts to increase the DOS environment size by increasing the "/E" paramenter of the SHELL statement in
CONFIG.SYS are ineffective.

Solution: Changes in the SHELL statement are not passed to secondary command processors invoked by various application
programs or by simply typing COMMAND at the system prompt. These secondary environments will be no larger than the amount
of space that was actually in use in the primary environment. In other words, the secondary environment has no extra free space.
Additional SET statements will return the "Out of environment space" error message. The solution to this problem is to increase the
default environment size by patching the byte that determines this DOS property. The location of this byte is version specific, so
you MUST follow the instructions for your version of DOS. Furthermore, if the problem is found in a network environment, you must
patch the command processor on each workstation that has the problem.

1.Insert a blank, formatted diskette in your A: drive. (You must use your A: drive for this.) 
2.At the system prompt, type the command: SYS A: <enter>. 
3.Leave the diskette in drive A: and restart the computer by pressing the reset button or by
pressing the Ctrl, Alt, and Del keys at the same time. 
4.If the system boots from the floppy correctly, you will probably see date and time prompts. Just
press <enter> when they appear. That should put you at an A:> prompt. 
5.Type VER <enter> to see what version of DOS you are using and note the version number. (If
your DOS is not MS-DOS 5.0, 6.0, 6.2, or 6.22, you cannot apply this patch. Call SOS to discuss
other approaches. 
6.Still at the A: prompt, type C:\DOS\DEBUG COMMAND.COM <enter>. The debug prompt ( a
hyphen or dash) will appear. 
7.The next commands will differ slightly depending on the version of DOS you are using. Be sure to
select the correct version below: 

MS-DOS 6.2 or 6.22:

D 1777 L 1 <enter> 

This command will display a memory address and a number to the right of the address.
This number should be "10". If not, something is not right, so just type "Q" and <enter> to
exit Debug. If the number is "10" then continue with the following commands.

E 1777 40 <enter>

W <enter>

Q <enter>

MS-DOS 6.0:

D 1767 L 1 <enter> 

This command will display a memory address and a number to the right of the address.
This number should be "10". If not, something is not right, so just type "Q" and <enter> to
exit Debug. If the number is "10" then continue with the following commands.

E 1767 40 <enter>

W <enter>

Q <enter>

MS-DOS 5.0:

D 1666 L 1 <enter> 

This command will display a memory address and a number to the right of the address.
This number should be "10". If not, something is not right, so just type "Q" and <enter> to
exit Debug. If the number is "10" then continue with the following commands.

E 1666 40 <enter>

W <enter>

Q <enter>

8.Still leaving the diskette in drive A:, reboot the computer again with the reset button or by
pressing the Ctrl, Alt, and Del keys at the same time. Once again, it should boot up, maybe with
time and date prompts and put you at the A:> prompt. If it does not, then perhaps you did not
follow the directions exactly. Try again from step one. 
9.Assuming that all is well and the computer rebooted properly, type DIR <enter> and check the
date next to the COMMAND.COM file. It should be the current date, indicating that the file was just
changed. 
10.Copy the patched version of COMMAND.COM to your hard disk with the following commands: 

COPY COMMAND.COM C:\ <enter>

COPY COMMAND.COM C:\DOS <enter>

11.Now remove the diskette and reboot the system normally so that it starts from the hard disk. You
have successfully increased the default environment size to 1040 bytes, which should be enough
for almost any application.