Dipa,
Well, you are in luck. You aren't the only one having this issue.
The error in your log is :
Note: 1: 1719
CustomAction SchedSecureObjects_x64 returned actual error code 1601 (note this may not be 100% accurate if translation happened inside sandbox)
MSI (s) (C4:1C) [22:20:37:333]:
Product: Microsoft .NET Framework 4 Client Profile -- Error 1719. The Windows Installer Service could not be accessed. This can occur if the Windows Installer is not correctly installed. Contact your support personnel for assistance.
Error 1719. The Windows Installer Service could not be accessed. This can occur if the Windows Installer is not correctly installed. Contact your support personnel for assistance.
There are tons of different fixes for this issue.
http://answers.microsoft.com/en-us/windows/forum/windows_other-windows_update/net-framework-40-install-failure/e3f08b40-3c88-427f-b8fe-8a9a4e770eba
To solve the error you will need to install the update by using standalone installer or setup file.
Access the below link to install Microsoft .NET Framework 4:
http://www.microsoft.com/downloads/details.aspx?FamilyID=0a391abd-25c1-4fc0-919f-b21f31ab88b7&displaylang=en
Check if you come across the error.
If the issue still persists, we might have to troubleshoot on Windows Installer.
Method 1
Make sure the Windows Installer service is not disabled.
1. Click Start, type Services in the search box.
2. In the Services (Local) list, right-click Windows Installer, and then click Properties.
3.If the Startup type drop-down list is set to a value of
Disable, select the Manual option from the Startup type drop-down list,
and then click OK.
4. Click the File menu, and then click Exit
Method 2:
If you still experience the issue, we might have to make little changes in the registry.
1. Click on Start, type regedit in the search box.
2. On the Registry Editor window, navigate to:
HKLM\System\CurrentControlSet\Services\MSIServer
3. Change the DisplayName value to:
C:\WINDOWS\SysWOW64\msiexec.exe /V
4. Close registry editor.
5. Now register the installer by opening a command prompt(Click on Start, type cmd in the search box).
C:\WINDOWS\SysWOW64\msiexec.exe /regserver
6. Type Exit.
If this fix does not work, continue googleing "
Product: Microsoft .NET Framework 4 Client Profile -- Error 1719"
I would also make sure that you turn of UAC in vista (I think that is what you are running) and see if that helps.
Let us know of your results.