energy resistance and multiple attacks from a single spell.

[Melvin the Mediocre]

Running a module, an adversary cast magic missiles that did fire damage and had scorching ray. Her target has fire resistance 5.

I believe that the magic missile spell was considered a single attack and therefor all missile damage was added up and resistance applied once. The scorching ray consisted of multiple attacks, each ray had damage rolled separately and resistance was applied separately.

I'm not sure if that is correct; should each missile have had resistance applied separately effectively giving the target immunity to her magic missile spell?

[SlimGauge]

I believe that each missile applies its damage separately.

[Fuzzy-Wuzzy]

Since the missiles could be directed at multiple targets I think they have to be considered separate attacks.

Effective immunity to somebody's metamagic'd magic missile spell isn't really a big deal.

[thorin001]

Apply it the exact same way you apply SR.

[wraithstrike]

I would say it applies separately.