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"invalid system disk, replace the disk, then press any key" message
spanky2 Apr-21-02 10:21 PM
My old P-133 using Win95 stopped booting up correctly.
After turing on computer, does mememory test, hard drive is ok. ( i checked CMOS)
I then get the message "invalid system disk, replace the disk, then press any key" and it won't boot up to Win95. (No disk is in drive)
Win95 boot up disk doesn t solve it. Checked for sys.com file on boot up disk, then typed a:\sys c:
Now when turning on computer, goes thru memory test, etc. says "starting windows 95..." then all I get is c:\ prompt. Still won't boot up and start Win 95. HELP?????
Dont think I have a virus. Heard of a virus that can affect needed boot up files. Anyway, would apreciate some help..........Thanks to everyone!

1. RE: "invalid system disk, replace the disk, then press any key" message
lbyard Apr-22-02 12:01 PM
In response to message 0
Likely causes are a defective drive, corrupted files, or a virus. I would start by running scandisk from a boot floppy. It would be a very good idea to back-up valuable data first (http://duxcw.com/digest/guides/hd/rules.htm). Larry

2. RE:
Twinhead Apr-22-02 03:05 PM
In response to message 0
LAST EDITED ON Apr-22-02 AT 03:53 PM (EST)
You have done ONE thing wrong!
You have actually replaced the IO.SYS and the MSDOS.SYS files on your hard drive with the "Sys c:" command!
That couses windows not to boot up anymore.
In the file MSDOS.SYS was a lot of data who is deleted beceause the amount of data on the file written bij SYS.COM is MUCH less.

Here is an example of My MSDOS.SYS . (I use Win98SE, but try to replace the version number of YOUR windows version)
This is found in the line starting with "WinVer=...."
Lines that do NOT appy on Win95 such as autoscan and doublebuffer are already deleted.
Symply, make an text file named "msdos.txt" (Without quotes!).
Copy the contens of this text between -Begin- and -End- in that file,
Save that file on the root of your C.

By the way, This forum seems to kill HTML!!
Replace IN the text "(" for LeftBracket, the key right next to "P"
Replace ")" for RightBracket, The key second-next to "P"
EXEPT for THIS line:
"Do not remove them (MSDOS.SYS needs to be >1024 bytes)."

enter at the c-prompt "attrib c:\msdos.sys -h -r -s" (Without quotes!)
rename the textfile to "msdos.sys" (Confirm Overwrite!)
enter at the c-prompt "attrib c:\msdos.sys +h +r +s"
Reboot and see.

;The following lines are required for compatibility with other programs.
;Do not remove them (MSDOS.SYS needs to be >1024 bytes).

Give it a try!

3. fdisk /mbr
lbyard Apr-22-02 03:37 PM
In response to message 2
I think I would back-up any data before executing fdisk /mbr. Although I have used the /mbr flag many times in the past without a problem, I have recently read (e.g., http://www.cknow.com/vtutor/vtfdiskmbr.htm and http://www.geocities.com/thestarman3/asm/mbr/FDISK.htm) that it can wipe a partition. What's your take on that? See help on using HTML with this forum. An aside… I’m still working on the flowchart. Larry

4. RE: fdisk /mbr
Twinhead Apr-22-02 03:47 PM
In response to message 3
LAST EDITED ON Apr-22-02 AT 03:55 PM (EST)
Ok Larry, i will see the URL involving Fdisk.
I am pleased to hear that you are working the flowchart out.
Correct anything you seem to be fit, I am dutch and can easely make errors in language.

(Back again)
I read that article on this.
Pfew, there is more than i could emagine of!
I Instantly removed that option in my post above.
I want to help, NOT to let someone destroy his drive at my advice.


5. RE: fdisk /mbr
lbyard Apr-22-02 03:59 PM
In response to message 4
Long, odd URL's don't always work right. There is way to directly input HTML, but I find it inconvenient. Overall, David Choi at dcscripts.com has done a very good job on the software. Larry

6. RE: fdisk /mbr
DJ Net2Infinity Apr-22-02 07:28 PM
In response to message 5
I always use the mbr switch as a very very last resort, but if a drive is dead and you have tried everything else what do you have to lose. I actually use a utility I got a few years back while working on SCO Unix servers that will back up and repair the master book record, it has come in extremely handy when I have stupidly written my lilo to my mbr on a dual boot system ( Thank goodness for Grub). I totally agree with those articles, but when you have nothing to lose what could /mbr hurt.

8. RE: fdisk /mbr
lbyard Apr-22-02 11:32 PM
In response to message 6
Agree that one could try the /mbr flag as a last resort or after backing-up data if it can be accessed. Larry

7. RE: fdisk /mbr
DJ Net2Infinity Apr-22-02 11:18 PM
In response to message 5
Microsofts Fdisk/mbr Opinion

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