Unable to control A20 line

[raindog1980]

Ciao a tutti, questo è il mio primo topic sul forum quindi è giusto che mi presenti: mi chiamo Marco, ho 24 anni e scrivo da L'Aquila.
Vi espongo il mio problema. Ho ereditato un vecchio portatile, un olivetti echos 46 color, con sopra installato windows 95. Il computer andava molto lento, c'erano molti programmi sopra, così ho pensato di reinstallare il sistema operativo, magari il windows 3.11 (tanto a me servirebbe solo per scrivere). Ad ogni modo ho fatto partire da floppy Partition Magic 4.0, ho formattato l'hard disk (che ha una capienza di 335 MB) ed ho creato una partizione FAT.
A questo punto ho provato ad installare sia windows 3.11 che windows 95 ma in entrambi i casi mi riporta il seguente errore:

ERROR: Unable to control A20 line!
XMS driver not installed

Ho trovato su internet le seguenti informazioni sul mio problema: The A20 line is the start of the first 64K of extended memory, known as the high memory area (HMA). The HIMEM.SYS device driver must control the A20 line to manage extended memory. The HIMEM.SYS driver reports the error if it incorrectly identifies the extended memory handling mechanism of the computer or if the handling method of the computer's BIOS is unknown.

Ma a parte questo non so come risolvere la questione, pertanto resto in attesa della vostra gentile collaborazione.

Ciao

[Dylan666]

Trascrivo perché già ho recuperato la pagina dalla Google cache, fra poco chissà se l ritrovo...

Error: "HIMEM.SYS is missing..." or "Unable to control A20 line..." after installing Norton SystemWorks

Situation:
After installing Norton SystemWorks and restarting the computer, you see one or both of the following error messages:

- HIMEM.SYS is missing. Make sure that the file is in your Windows directory.
- Unable to control A20 line. XMS driver is not installed.

Solution:
This problem is caused by differences in the BIOS chips that are included with computers.

To solve the problem, turn the computer off and wait 30 seconds before turning it back on. While it is off, unplug the keyboard and plug it back in.This step may solve the problem for some computers, such as computers that use the NVIDIA nForce chipset.

If this does not solve the problem, use the following procedure to make changes to the computer's startup files.

To edit the startup files:

Restart the computer in Safe mode Command Prompt Only:
Click Start, and then click Shut Down. The Shut Down Windows dialog box appears.
Click Restart, and then click Yes. Windows will shut down and the computer will restart.
For Windows 95: When "Starting Windows 95..." appears on the screen, press F8. The Windows 95 Startup Menu appears.
For Windows 98: As the computer restarts, press and hold down the Ctrl key until the Windows 98 Startup Menu appears.
Select Safe mode Command Prompt Only, and then press Enter. Windows will display a DOS prompt.


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Note: In Safe mode, Windows uses default settings: VGA monitor, no network, Microsoft mouse driver, and the minimum device drivers required to start Windows. You will not have access to CD-ROM drives, printers, or other devices.
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Add a line to the Autoexec.bat file:
Type edit autoexec.bat to open the Autoexec.bat file in the DOS Edit program.
Type set dos16m=2 as the very first line in the file.
Press Alt+F to open the file menu, and then press S to save the file.
Press Alt+F to open the file menu, and then press X to exit the editor.
Restart the computer to see whether the problem is solved. If not, then continue with step 5.
Restart the computer in Safe mode Command Prompt Only:
Click Start, and then click Shut Down. The Shut Down Windows dialog box appears.
Click Restart, and then click Yes. Windows will shut down and the computer will restart.
For Windows 95: When "Starting Windows 95..." appears on the screen, press F8. The Windows 95 Startup Menu appears.
For Windows 98: As the computer restarts, press and hold down the Ctrl key until the Windows 98 Startup Menu appears.
Select Safe mode Command Prompt Only, and then press Enter. Windows will display a DOS prompt.


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Note: In Safe mode, Windows uses default settings: VGA monitor, no network, Microsoft mouse driver, and the minimum device drivers required to start Windows. You will not have access to CD-ROM drives, printers, or other devices.
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Verify that the Config.sys file has a line for the Himem.sys file:
Type edit config.sys to open the Config.sys file in the DOS Edit program.
The Config.sys file should include the following line. You may need to append a space and /M:1 only or add the entire line.

device=c:\windows\himem.sys /m:1

Press Alt+F to open the file menu, and then press S to save the file.
Press Alt+F to open the file menu, and then press X to exit the editor.


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Note:
If Windows is installed to a different folder, then substitute the appropriate folder name.
The value for the /M: parameter can range from 1 to 17. The value of 1 works for most computers. IBM PS/2 and Compaq Prolinea computers may require a value of 2.
If a value of 1 or 2 does not resolve the problem, try each of the other values up to 17.

[Dylan666]

Guarda pure qui

[Sergio1983]

Eventualmente controlla che nel BIOS non siano presenti voci che autorizzano l'uso della linea A20 (lo spazio di memoria di 64 Kb appena sopra il primo Mbyte di RAM, usato dai tempi del DOS per contenere il kernel del SO, liberando preziosa memoria convenzionale) per funzioni di shadowing, impedendone l'uso al sistema operativo.

Trascrivo perché già ho recuperato la pagina dalla Google cache, fra poco chissà se l ritrovo...

Il mod sei tu, mica ti devi giustificare...