Unable to access the Gem Store
You can try clearing the GW2 cache (instructions found [for Windows] in the Knowledge Base accessed via the ‘Support’ link above/below).
Good luck.
Well, to be honest, given that I’m on a Mac, instructions for Windows aren’t particularly helpful, but thank you for the help! Do you know where equivalent instructions are?
Well, maybe you can look at the Windows instructions and apply it to Mac processes.
You can contact the Tech CS Team via the same link.
Good luck.