I think, now, though, I finally managed to discover the root of the problem, and hopefully (knock on wood), my printer will be headache free. This post is primarily to put in one place the information I used so that should this irritating printer failure occur again I won't have to waste my time searching the internet once more.
Anywhoo, I think the issue is that my computer was giving the printer a new IP address with every boot-up. Why it started doing this a year ago when previously it hadn't still remains a mystery. I blame a Windows update somewhere along the line.
- Press "Go" button on printer 3 times within 2 seconds to print "printer settings". Check for IP address and "Boot Method" status.
- If "Boot Method" status is "Auto", it needs to be changed to "Static". To change Boot Method on Windows 7: go to Control Panel -> Network and Internet --> View network computers and devices under Network and Sharing Center. Right click on printer --> click 'view device webpage'. Browser window should open, just like when accessing router settings. Click on Network Configuration on webpage --> Configure TCP/IP under Wired (the printer is connected by network cable) --> change Boot Method to 'Static' --> click 'Submit' and exit.
- Next, go to Devices and Printers in Windows 7 --> right click on printer --> Printer properties --> Ports --> Add Port --> choose 'Standard TCP/IP Port' and then click New Port --> Wizard will pop up, click 'next' --> and under 'Printer name or IP address' type in the IP address of printer found in printer settings (see step 1) --> click 'next' then 'finish'.
- Confirm new port created by making sure the new port is listed under Ports, and check off the box next to it. Choose this new port and click Configure Port --> make sure under 'Protocol' that the 'RAW' radio button is chosen. Everything else should be default, eg. SNMP status is 'enabled' (Community name = 'public'; SNMP device index ='1'). Click 'OK'.
Oh yeah. Print out whatever I need to print before restarting computer. Just in case.