This answer was posted a while ago;
---------------------------------
Remove and reinstall Office 2003
======================
1. Download and install the Windows Installer Cleanup Utility.
<
http://download.microsoft.com/download/E/9/D/E9D80355-7AB4-45B8-80E8-983A48D5E1BD/m
sicuu2.exe>
2. After you install the Windows Installer CleanUp Utility, click Start
menu-> All
Programs-> Windows Install Clean Up.
3. Highlight Microsoft Office 2003 entry in the list and then click Remove.
Quit
the Utility.
Note: If you have got any other old or redundant office entries or other
Office
stand alone products such as FrontPage, Visio, OneNote, etc in the list,
please
remove them together.
4. Close all applications.
5. Click Start menu-> Run, type "regedit" (without the quotation marks) in
the Open
box and press Enter.
6. Expand the registry tree on the left pane and locate the following two
registry
keys:
HKEY_CURRENT_USER\Software\Microsoft\Office
HKEY_LOCAL_MACHINE\Software\Microsoft\Office
7. Right-click on this key and click Delete to delete those keys.
8. Open Windows Explorer, and then browse to the "C

Program Files" folder
If it exists, rename the "Microsoft Office" to "Microsoft Office OLD"
If it exists, rename "OfficeUpdate" to "OfficeUpdateOLD"
If it exists, rename "OfficeUpdate11" to "OfficeUpdate11 OLD"
9. Click Start menu-> Run, type "%Temp%" (without the quotation marks) in
the Open
box and press Enter.
10. Empty the %Temp% folder.
Note: If some files can't be deleted, please skip them, which don't
influence the
result of the troubleshooting.
11. Empty the Recycle Bin.
12. Restart your computer and install Office 2003.
I hope that this helps resolve your issue.
Regards,
Rick
"Steve Grech" <SteveGrech@discussions.microsoft.com> wrote in message
news:7761DB9C-2DFD-4DF4-AB21-B96B1CC53B04@microsoft.com...
> Hi DL...yes I did also uninstall the Activation Assistant...still no
> success...Steve
>
> "DL" wrote:
>
>> Did you also uninstall the Activation Assistant?
>>
>> "Steve Grech" <SteveGrech@discussions.microsoft.com> wrote in message
>> news
C1F1C07-30C6-407B-A2E8-67A2F681C736@microsoft.com...
>> > Hi. .I am still unable to install..
>> >
>> > I uninstalled the trial version of Office that was installed by HP on
>> > this
>> > new PC. and rebooted.
>> >
>> > The same following error messgae comes up when installing 2003.
>> > Ïnstallation error: File not found
>> >
>> > A required unstallation file CS561404.CAB could not be found
>> >
>> > Original Installation source required:
>> > If you installed Microsoft Office Standard Edition 2003 from a CD,
>> > please
>> > insert you CD ..etc
>> > Once you have located your installation source click OK.
>> >
>> > So I clicked OK....nothing.
>> >
>> > I find the CAB file in the CD file list...still nothing.
>> >
>> > Your help would be really apreciated.
>> >
>> > Thanks Steve
>> >
>> >
>> > "Steve Grech" wrote:
>> >
>> >> Microsoft Office Student and Teacher Edition 2003 will not load on
>> >> Windows
>> >> Vista Home Premium - During installation it comes up with an error
>> >> message
>> >> wanting a file called CS561404.CAB
>> >>
>> >> Please help
>>
>>
>> .
>>