Brother MFC990CW Printer loses connection

Went out to a customer's yesterday because her printer would not print wireless on any computer. She has 2 windows 7 computers, and 1 windows 8. The wireless router regretfully, I did not write down the model number but it was white, and the last part was 6600. She said she bought it about a month ago. The printer is a Brother MFC990CW.

So when I went out there yesterday, the static IP address was set to 192.168.0.1, the same static as the router. Changed it to 192.168.0.45. Added new printer on all computers, worked great.

She turned off the computers, and the printer last night. Turned them on today, and it once again wouldn't print. I walked her through the settings on the printer, it is still set to .45. Remote in, and checked the settings on the computer, it still looks good. Checked the settings on the router, it shows the printer just fine. Just because, I add a new printer, it found it in 2 seconds, set it up, and printed test page. 

Obviously, this is not something the customer wants to do everyday. What are some reasons the computers will no longer print to it unless you add it again?

comment:

1. Update router firmware?

Is the static IP that has been set, within the DHCP scope?

What firewall is on the PC?

Andy

2. I'm thinking duplicate ip and when the other device is online the printer stops. If it's only those devices then maybe not. Weak wireless signal from the printer to the router and it's dropping offline?

3. Just get the latest drivers from Brother and install them on every pc that needs to print.

Until a few years ago I used to set up printers manually but find less hassle using the install disk.

4.The computers all use ip addresses in the 100 range. I verified the router was up to date, and all the drivers I downloaded and installed yesterday. The printer is 3 feet from the router, so I can't imagine a weak signal. When it refuses to print, the printer shows it is connected and online. It is just the computer can't talk to it with yesterday's settings, which are the same as today. I verified when I clicked add printer. I then did a side by side comparison on the new printer and the old printer. Ports are all the same, everything is the same.

5. Try using an Ethernet cable instead of the printers WiFi.