You need to be completely stock, unrooted 4.0.3 for this update to work. If not, flash the 4.0.3 ota, reboot your device. Once done flash cwm via fastboot and then flash the update. Worked perfectly for me. You will need to root again though, but it's as easy as flashing superuser via cwm.
Although a quick loom through the xda nexus s development forum has a flash able zip of the update which is even easier.
With my Nexus S for Tmob it was rooted, tried to basically unroot and flash down to the stock then upgrade to the 4.0.3 manually but that is not working. Also, I locked the bootloader to try and see if it will work. Unsuccessful in getting the the OTA 4.0.4 to install as well. Any suggestions? Thanks.
I'm another Tmo Nexus S owner who had manually installed ICS 4.0.3 when it was first available back in December 2011. Two days ago (Mon Apr 2 2012) I got an automatic update to ICS 4.0.4. Yesterday I saw that Google+ was the biggest battery user & since I don't use it I disabled it, because I wasn't allowed to uninstall it.
Since disabling Google+ I've been surprised that the built-in Gallery application is the largest drain reported by on my Battery status page. This morning the phone has been unplugged for about 2.5hrs, and Gallery is at 69%. Next is Wifi at 7%, Cell standby at 6%, Screen at 6%, then Android System, Phone, and Android OS all at 3% each.
I never use the Gallery since I prefer QuickPic. But I can't disable or uninstall Gallery, and if I Force Stop it I'll still see it running when I check a few minutes later. I checked my three Gmail accounts under Gallery Settings and none of them are set to sync - Sync is OFF for all three Gmail accounts in Gallery.
Since it's the most obvious explanation, I'm guessing that disable Google+ has caused a problem with Gallery, but my battery drain will be bad again if I re-enable Google+. Anyone else seeing this sort of thing with ICS 4.0.4?
Nope, not having any battery drain issues. I had a lot of drain when ICS was first pushed, but it's been better as of late even before the update to 4.0.4. Since 4.0.4 the battery rate has been pretty close to my Ginger bread days. I still have 30%-40% left after 18 hours.
I see idle/wifi and sometimes Maps as the big drainers.