Hi, Hoping for some advice. I'm running a macbook pro on OS Maveriks and an iMac on Mountain Lion. (I know I'm not very up to date with the OS but I have some older software running that I don't want to have to upgrade). Long and short of it is: Files I have created in Microsoft office Excel on my Macbook will not open if copied across to my iMac. They will open fine if i just open from the external hard drive but if i actually copy or move the file they become Read only or something and refuse to open unless i do it in Numbers. I have the same version of MS office installed on both machines. i have tried opening the "Get-info" window and making sure all permissions say read-and write but I still can't open them unless I do it from the external drive. Any help would be amazing as its really annoying.