Just for posterity, your problem was not with atom types but with atom names. These are two different concepts, since atom type is a force field parameter concept related to LJ terms.
For SPC/E, look in the spce.itp file:
[ atoms ]
; nr type resnr residue atom cgnr charge mass
1 OWSPCE 1 SOL OW 1 -0.8476
2 HWSPCE 1 SOL HW1 1 0.4238
3 HWSPCE 1 SOL HW2 1 0.4238
Although we provide this topology if users want to try it, I would strongly urge you to use the validated water model for use with CHARMM36, which is the CHARMM-modified TIP3P (the default in tip3p.itp that we distribute with the CHARMM force field). Use of SPC/E is essentially untested and you run the risk of invalid simulations.