Solved

Error says Unable to control A20 line

Posted on 1998-06-30
3
379 Views
Last Modified: 2010-04-27
I'm trying to upgrade an old 486 I got free. But when it boots it says "Error Unable to control A20 line. XMS driver not installed." So emm386 does not install either.

I've checked config.sys. The appropriate lines are there, lines 1 and 2, for himem.sys and emm386. The latter has noems and highscan. I've tried with and without noems and highscan.

The files are where they should be. I recopied them in case they were corrupt.

After getting the 486, I changed out the controller card, 3.5 floppy, and installed an old SoundBlaster card and new CD. All work in dos just fine, and pass diagnostics. The system is dos 6.22 and win 3.11.

The pc was formerly on a network, and I've tried to remove all network references, as it isn't on a network now and doesn't have a network card at present.

What can I do to get himem to load?
0
Comment
Question by:Puffin1
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
3 Comments
 

Author Comment

by:Puffin1
ID: 1019542
Edited text of question
0
 
LVL 1

Accepted Solution

by:
sKiiKe earned 50 total points
ID: 1019543
Try

DEVICE=C:\DOS\HIMEM.SYS /A20CONTROL:OFF

or
DEVICE=C:\WINDOWS\HIMEM.SYS /A20CONTROL:OFF

Also You could try
the same lines with /MACHINE:?? , with ?? being numbers 1-17. If these do not help, I would suspect memory troubles


0
 

Author Comment

by:Puffin1
ID: 1019544
I tried the first option, adding /A20control:off and even though it goes through the initial memory check okay, it now hangs in bootup at "HIMEM checking extended memory". So now I can't edit config.sys.

I checked to see if the memory modules (4 30 pin 1x9s) were seated okay. I had taken them out to see if I could use some other memory I had, but they didn't work, so I replaced them.


0

Featured Post

Instantly Create Instructional Tutorials

Contextual Guidance at the moment of need helps your employees adopt to new software or processes instantly. Boost knowledge retention and employee engagement step-by-step with one easy solution.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This is about my first experience with programming Arduino.
Stuck in voice control mode on your Amazon Firestick?  Here is how to turn it off!!!
A short tutorial showing how to set up an email signature in Outlook on the Web (previously known as OWA). For free email signatures designs, visit https://www.mail-signatures.com/articles/signature-templates/?sts=6651 If you want to manage em…
How to Install VMware Tools in Red Hat Enterprise Linux 6.4 (RHEL 6.4) Step-by-Step Tutorial

696 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question