I have had troubles running SW2011 service packs 0,1, and 4. Mostly occasional freezes, but it got much worse lately so I figured it was time for a system re-install (it's been a few years and i had SW2010 and 2011 on the CPU).   Today I wiped my system, fresh install of Win7 Pro, and started installing SolidWorks.  I used the DVD, and tried selecting the straight online update to SP5, hoping it would circumvent any issues I had with SP4.  The installation failed, so I installed SP0 from the DVD, then tried downloading and installing SP5.  It failed multiple times giving me "Error Writing to file", for files such as sldanalysistools.dll, slderresu.dll.  I tried skipping files, but just had more errors.  I aborted the update, then tried disabling antivirus (MS Security Essentials), and ran the SW installation manager->check for updates as Administrator.  I am still getting error 1310 error writing to file, The Installation Manager does not have permission to modify this file.  Any deas?  Install logs attached.