HP T1200

[Hendrik1974]

I have an HP T1200 designjet that is giving a error code 79.04 with startup

I have removed it from the network and res

[D Hook]

That error code is probably one of the most difficult ones to trouble shoot because it's so general in nature and difficult to pin down the cause.  HP has about a 13 page explanation and "fixes" in their Service Manual.  Info you want is on Page 77, Appendix A: How to troubleshoot SE 79:04.  They say it's rarely a hardware issue and almost always attributed to a software/firmware issue.  Here's a link:

https://www.dectrader.com/docs/set08/408048/hp-designjet-t770-t1200-service-manual.html

They recommend an update to the firmware, even if the printer is displaying the latest version.  They also recommend checking the file you're printing to be sure it's a compatible format.  For instance, if you're sending a file that requires the PS option on the printer and you don't have the PS option, it may cause this error to display.  Can also be a network problem, if the printer is networked.  Do you have the printer set up so you can utilize the EWS (Embedded Web Server) feature?  Easiest way to upgrade the firmware.

You'll want to download the manual and read through the section on the 79:04 error.  It could be something very simple like the aforementioned file problem.  Let us know what you find.

[Hendrik1974]

Thank you very much. D Hook

I think the link might be the wrong one. It's only from page 158 to page 177.

I downloaded the latest firmware from the H website for this printer and copied it to a usb drive. Plugged it into printer and started it up. IT gave me the option to install the latest firmware and I clicked on OK. There was a message that said I must remove the usb drive, then I received a message "Inserted USB Flash drive does not contain valid firmware file. (TT6-TTAJ_08_04_00.1_mvl40-x86-opt_B.signed)

I am a bit stupid when I comes to embedded wbb server. Not sure what that is. 

[D Hook]

Not sure why that link is only for those pages.

Try this one:  https://all-guidesbox.com/download/1027225/hp-t770-service-manual-383.html

If it says Designjet T770, you can choose that option.  The manual covers both machines.

If that doesn't work, just google "T1200 Service Manual" and it should come up.  There will be a few options, some are free and some are behind a paywall.  

The thumb drive you use must be completely empty, no other files present except the firmware file or it won't work correctly.

For the EWS, the printer needs to be connected to the internet with a cat 5 cable.  I usually just plug mine into the Cat 5 input on the back of my computer because I use a wireless router to connect the computer to the internet.  You should see an ISP number in the display panel on the front of the printer.  Go to your  browser and enter that number; no "WWW" or HTTP:" prefix, just the number.  It should connect to the printer and display a front page of the EWS.  The owners manual, if you still have it, shows the setup for the EWS.  If you don't have the owners manual, it's on the HP website.

[D Hook · Accepted solution]

Here's another source for that service manual:

https://cdn.shopify.com/s/files/1/1083/1086/files/T770_T1200_service_manual.pdf?9878984334271461826

[Hendrik1974]

Hi D Hook

Finally it is working again. It was a data relate issue. 

4.    If step 3 did not resolve the issue, you can check the hard disk's file system.
a. Start the printer in Diagnostics Boot Mode.
b. Perform a File System Check. This will fix any error in the file system structure. It may take a
few minutes, or up to an hour, depending on the state of the hard disk.

[D Hook]

Good deal.  Those are great printers.