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@HydroSky Sounds like a scripts issue yes. Do you have scripthook and community scripthook 3 installed? They should be installed to your GTA 5 root folder. Also in your root folder should be the scripts folder. And that folder MUST say scripts in all lower case letter. Inside the scripts folder should be the OceanGateExpeditions folder and the Naudio.dll.

@HydroSky Hello and sorry you are having some problems. To turn on MP maps, you need a mod like Simple Trainer:
https://www.gta5-mods.com/scripts/simple-trainer-for-gtav

It has options in its menu to turn the MP maps on and off. When you first load your game, do you see a notification above the mini map that says "OceanGateExpedition"? When you stand in front of the desk at the office, or when walking around the desk, you never see a notification to open the menu? I am first trying to determine if your script is running. If you see the office, the DLC is properly installed, but you might have a problem with your script setup.

@KSIhairfine123 Well hombre it looks like this is where we part paths. You see, I tend to look into people when they ask me for help. It allows me to see what tech level I should be prepared to work with in solving an issue. After seeing your comments and choices of words on several mods recently, I would rather you uninstall our subs and not use them anyway. I have family that is part of the community people like you are so afraid of. So just leave your little comments and move on pardner.

@KSIhairfine123 At what point does it abort? After you select an expedition or before the menu shows? If you have all the required files, lets just make sure you didn't miss a step. You MUST make sure you have the no boundary mod installed and your game should have MP maps enabled. You also MUST have a version of GTA new enough to contain Cayo island. If ANY of the resources from that update are missing, the script cannot get the files it needs to start. Also, make sure you put the ENTIRE OceanGateScripts folder into your scrpts folder. So the installed path for the script folder should be: Grand Theft Auto V/ scripts/ OceanGateScripts/ .. Make sure you @ me so I know ya need something. I don't come in here every day otherwise.