These errors typically occur when security software interferes with the restore and update process. Use the steps to troubleshoot security software issues to resolve this issue. In rare cases, these errors may be a hardware issue. If the errors persist on another computer, the device may need service.
Also, check your hosts file to verify that it's not blocking iTunes from communicating with the update server. See the steps under the heading "Blocked by configuration (Mac OS X / Windows) > Rebuild network information > Mac OS X > The hosts file may also be blocking the iTunes Store." If you have software used to perform unauthorized modifications to the iOS device, uninstall this software prior to editing the hosts file to prevent that software from automatically modifying the hosts file again on restart.
error 29 is battery issue try to replace battery w/ 80 percent charge or replacee a new one for error 3194 ios 7.0.2 is software issue because 7.0.2 is stop signing in server. better go for latest ios 7 of apple.
Check R61 and R153 next to battery connector they are 0 ohm resistor links that go to U52 and tell the chip the state of the battery.
if either of these are broken or cracked, the restore will fail at about 70% with error 29
check your restore log...
'RamrodErrorDomain/3ea: update_gas_gauge: gasgauge_swupdate returned -1'
Replacing or bridging these resistors wil fix it. It worked for me anyway