I am attempting to install SQL Server Express (as part of the Visual Studio 2010 Professional installation), but it is failing. I am receiving this error log.

[06/22/11,16:31:39] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab
[06/22/11,16:31:40] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD}
[06/22/11,16:32:12] setup.exe: [2] Duplicate component in install order: SQL EULAs
[06/22/11,16:32:12] setup.exe: [2] Duplicate component in install order: SQL EULAs
[06/22/11,16:32:12] setup.exe: [2] Duplicate component in install order: SQL EULAs
[06/22/11,17:07:55] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab
[06/22/11,17:07:55] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD}
[06/23/11,10:39:33] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab
[06/23/11,10:39:33] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD}
[06/23/11,10:40:22] setup.exe: [2] Duplicate component in install order: SQL EULAs
[06/23/11,10:40:22] setup.exe: [2] Duplicate component in install order: SQL EULAs
[06/23/11,10:40:22] setup.exe: [2] Duplicate component in install order: SQL EULAs
[06/23/11,10:53:48] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab
[06/23/11,10:53:48] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD}
[06/23/11,13:19:26] Microsoft Visual Studio 2010 Professional - ENU: [2] UpdateFileFetcherFromMsi: Warning: Missing fwlink entry for cabinet: #SP.cab
[06/23/11,13:19:26] setup.exe: [2] Duplicate module ID: {0AFE11CA-57AA-4F66-90BE-284F0F3A5ABD}
[06/23/11,16:47:36] Microsoft SQL Server 2008 Express Service Pack 1 (x64): [2] Error code -2068643839 for this component is not recognized.
[06/23/11,16:47:36] Microsoft SQL Server 2008 Express Service Pack 1 (x64): [2] Component Microsoft SQL Server 2008 Express Service Pack 1 (x64) returned an unexpected value.
***EndOfSession***

I'm reading various articles which point towards something being wrong in the register, but I can't find anything specific. Any suggestions for what I can do to fix this?