🚀 go-pugleaf

My sister has almost her entire c:  hard drive (all but a few kbytes)
formatted as a DoubleSpace volume.  I managed to screw up her
config.sys (I added a device= statement which (I guess) is causing it
to try to load a driver which is not really a driver) so that now she
can't boot from it.  And I know almost nothing about DoubleSpace.

When we boot from a floppy, we're able to view the directory on the c:
drive, but the only things that show up are the few hidden files needed
by DoubleSpace.  That means (I guess) that the config.sys is saved within
the DS volume.  But I need to be able to edit it to remove this invalid
device= statement, and I don't know how to get access to it.

We ran SCANDISK against both the c: drive and the DoubleSpace drive on c:
and SCANDISK reported that both volumes were ok.  After scanning the DS
drive, it said that the volume wasn't mounted and that we should mount it
with the command:
   DBLSPACE/MOUNT C:

When we issue that command, we get the message:
-=-=-=-=-
There are no more drive letters reserved for DoubleSpace to use.  To add more
drive letters, choose the Options command from the Tools menu.
-=-=-=-=-

I tried issuing the command:
   dblspace/mount c: /new=h:
but got the same message.

The config.sys on the floppy that we're booting from looks like:
   LASTDRIVE=M
   DEVICEHIGH /L:1,39488 =A:\DOS\DBLSPACE.SYS /MOVE
(we're booting from a:)

We tried issuing the DBLSPACE command with no parameters, too.  I don't
have the exact message text, but it complained that it couldn't run
when booting from a floppy, and refused to start up.

Does anyone have any suggestions they can offer on how I can get access
to the config.sys on this DS volume?  What's the Tools menu?  How can
I reserve more drive letters?  Is that the right approach, or should I
try something else?

We're really getting pretty desperate.  Any suggestions would be greatly
appreciated.

Thanks very much.
Bill