SQL Server 2008 upgradation error from SP1 TO SP3

HI,

I am getting below error while upgrading service pack from sp1 to sp3 .

TITLE: SQL Server Setup failure.
------------------------------

SQL Server Setup has encountered the following error:

The cached patch file "C:\Windows\Installer\3f9e306.msp" is missing.
 The original file for
 this cached file is
 "sql_engine_core_inst.msp", which can be installed from "", 
version 10.1.2841.0.

For more information about how to resolve 
this problem, 
see “Steps to resolve missing media issue with SQL Server 2008” 
(http://go.microsoft.com/fwlink/?LinkId=144387)
 in the Microsoft Knowledge Base.

Error code 0x84B20003.

------------------------------
BUTTONS:

OK
------------------------------

I have referred the link mentioned in the above error and provided the required patch file to the windows installer.

but after that  I am getting following error.

SQL Server Setup has encountered the following error:

The system cannot open the device or file specified.

Please help.