Welcome to IPCT!
I assume you're using
Blue Iris since you are in a Blue Iris forum.
@SouthernYankee has asked some important questions about Wi-Fi and camera settings because it's likely your wireless network cannot handle all the data that the cameras are supplying.
1) Did the cams work fine for a time and then Blue Iris just recently began displaying this error or is this the first time you have tried to connect these cameras to Blue Iris?
2) Can you provide a screen shot of one of the camera's "properties", "video" tab, "configuration" ?
3) back to the wireless issue: have you tried unplugging (turn off) 3 of the cams and disabling those 3 in Blue Iris to see if 1 cam will work OK?
4) Did you ever set up P2P on any camera(s) by scanning a QR code or entering a camera ID / serial number in a smartphone app?