Windows 7 Service Pack 1 error 80004005

Folks, I believe I have an answer to the problem. After trying many different options suggested above without success, I managed to install the service pack. As mentioned in a number of previous messages, the system partition is  the root of all evil. The system partition (this is not the partition that has win7 installed) is either too small or is full. You need a minimum of 20M or more for the install to work. My system partition was 100M in size and had only 5M free, this caused the service pack install to fail with the messages indicated above. On freeing up space (20M availability) the install worked successfully. To access the system partition (has no assigned drive letter) you need to use the win7 partition manager software found in the control panel, assign a drive letter to system partition, access the new partition, move a larger enough file from one of the directories onto a win7 partition, freeing up space, run the service pack install, installation should succeed. After rebooting from service pack install , reverse the process, copy file back to system partition and remove the assigned drive letter. All complete ............hope this helps!!!!!