Windows XP with SP3 updates.
This error keep coming up and stop the AdvertureWorks2008 db from installing. Why?
 
Error: Unable to open the physical file "C:\Program Files\
Microsoft SQL Server\MSSQL10.MSSQLSERVER1\MSSQL\
DATA\Documents
". Operating system error -2147024891: "0x80070005(Access is denied.)".
 
Installation Terminated
 
<?xml version="1.0" encoding="utf-8" ?>

• <DatabaseManifest xmlns="http://schemas.microsoft.com/sqlserver/2009/10/adventure-works/database-manifest">
  <InstallerTitle>SQL Server 2008 SR4 Sample Databases</InstallerTitle>
  <DefaultScriptInstallPath>Microsoft SQL Server\100\Tools\Samples</DefaultScriptInstallPath>
  <RequiredMajorVersion>10</RequiredMajorVersion>
  <RequiredMinorVersion>0</RequiredMinorVersion>
  <BuildNumber>91209</BuildNumber>
• <Database>
  <DatabaseName>AdventureWorks2008</DatabaseName>
  <PrettyName>AdventureWorks OLTP 2008</PrettyName>
  <SourceDatabaseScriptRelativePath>AdventureWorks 2008 OLTP\instawdb.sql</SourceDatabaseScriptRelativePath>
  <TargetDatabaseFile>AdventureWorks2008_Data.mdf</TargetDatabaseFile>
  <TargetDatabaseFile>AdventureWorks2008_Log.ldf</TargetDatabaseFile>

                                                                       "This directory"
                                                                                  |
                                                                                  V

  <TargetDatabaseAdditionaiDirectory>Documents</TargetDatabaseAdditionaiDirectory>
  <IsOLAPRequired>false</IsOLAPRequired>
  <IsFTSRequired>true</IsFTSRequired>
  <IsFileStreamRequired>true</IsFileStreamRequired>
  <IsEnterpriseRequired>false</IsEnterpriseRequired>
  <IsStandardRequired>false</IsStandardRequired>
  <ApproximateMessageCount>600</ApproximateMessageCount>
  </Database>
• <Database>
  <DatabaseName>AdventureWorksDW2008</DatabaseName>
  <PrettyName>AdventureWorks Data Warehouse 2008</PrettyName>
  <SourceDatabaseScriptRelativePath>AdventureWorks 2008 Data Warehouse\instawdwdb.sql</SourceDatabaseScriptRelativePath>
  <TargetDatabaseFile>AdventureWorksDW2008_Data.mdf</TargetDatabaseFile>
  <TargetDatabaseFile>AdventureWorksDW2008_Log.LDF</TargetDatabaseFile>
  <IsOLAPRequired>false</IsOLAPRequired>
  <IsFTSRequired>false</IsFTSRequired>
  <IsFileStreamRequired>false</IsFileStreamRequired>
  <IsEnterpriseRequired>false</IsEnterpriseRequired>
  <IsStandardRequired>false</IsStandardRequired>
  <ApproximateMessageCount>34</ApproximateMessageCount>
  </Database>
• <Database>