Unfortunately, the error you describe is more complex to fix than
you're probably bargaining for. I found the following information
about the error:
(Please note, all text between the !==*==! marks are copied from the
site the link leads to.)
Windows XP Service Pack 1 Known Issues
Partition Magic makes changes to the registry. These changes take
place during the process of resizing a partition. It is possible
other changes made by Partition Magic also make registry changes, but
this is only known instance where an issue has come up. This change to
the registry has been present when using Partition Magic, however has
not caused any known issues that we are aware of in prior releases of
our operating systems.
Build 1079 and later versions of the service pack will expose this
registry change with an error. When you install Service Pack 1 for
Windows XP you will get the following error message. "System could not
allocate the required space in registry log."
Build 1079 presents this error. Build 1050 did not.
Build 1089 and later builds have a workaround in place for people did
not run into this problem with 1079.
Steps to reproduce: Run Partition Magic and resize the partition. When
Partition Magic runs it modifies the system hive of the registry.
Partition Magic makes changes to the registry at boot time before the
OS is loaded. They rename the registry mounteddevices key.
The MountedDevices key is later renamed back. A new key is left in
place MountedDevice1 for trouble-shooting purposes. The way the
registry is modified affects the changes in build 1079 when we look at
the LastKnownGood entry. The entry is not at the expected location,
thus the error is generated. We can work around the issue in the next
release of Service Pack 1 by making changes to mounteddevice1 registry
Resolution: The built in workaround only applies to systems that did
not previously install 1079 and ran across the registry error message.
If the user previously had the error. "System could not allocate the
required space in registry log." you may not be able to install the
service pack unless you restore from an image without any previous
1079 installation failures.
This is due to uninstall failing to complete properly and leaving the
system in a partially installed / uninstalled state. If the uninstall
actually succeeded, it may very well be possible to install build 1089
or a later version of the service pack. However, all internal attempts
to install the service pack after this type of failure were
unsuccessful. Booting with last known good also failed to resolve this
This key is not used by the OS and is left on the system only for
trouble-shooting. This registry entries will be fully fixed with
Service Pack Two for Windows XP and will be fully fixed in Windows
.NET. Powerquest is working on resolution that will prevent this from
happening and will update their software."
So, the quick answer to the problem is to attempt to uninstall Service
Pack 1, and reinstall the latest Service Pack 1a in your install of
XP. HOWEVER, this is NOT an especially safe thing to do: you may cause
more problems than you solve.
Second solution MIGHT be the floppy boot disks. However, there's no
guarantee that they will work either--as you can see from the above
quote, in the 'resolution' section, there is no mention that a
boot-disk approach will work any better.
You also MIGHT be able to save a step and lots of hair-pulling by
trying to install SP1a over top of your SP1 install. The download page
for SP1 can be found at:
I'd recommend doing the "Network Install" and forcing a full/complete
reinstall of SP1a. That might help with the issue.
Failing the above, complain to PowerQuest and ask for a refund and/or
a bug-fix that will work around the known SP1 issue from Microsoft.
If any part of this answer is unclear, please let me know by asking
for clarification prior to rating and closing this question.