Hi I've not used my account for a while and now when I come to use it, I put my password in and it says 'Oops! Google Chrome could not find zp-core' - How can I access the admin section to alter items in my gallery? :/

I don;t know what I'm supposed to do now - I can;t change any of my gallery? It must be something so simple - can anyone help ,, Anna

Does the install work besides that? Also please provide minimum info about your install and the exact problem.
http://www.zenphoto.org/news/general-contributor-guidelines#reporting-bugs

zp-core is of course the base of Zenphoto, if that is missing it would be no surprise if nothing would work.