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Creality Print or Creality Cloud will not send the print (Upload Failed, Send Failed) or the printer shows offline

Guide based on the manufacturer's official documentation; usi3d has not yet verified it on a machine.

Technology: FDM · Brand: Creality · Symptoms: Does not connect to Wi-Fi or the app, The printer shows an error code or message · Updated on 9 October 2026

Symptom

When sending a job from Creality Print over the local network or the Internet you get «Upload Failed» or «Send Failed» with a number in brackets (7, 9, 25, 26, 28, 55, 56, 1001 or 20008), the software does not show the printer even though you entered its IP, or Creality Cloud shows it as offline after updating it or when binding it.

Likely causes, from most to least likely

  1. The printer is not connected to the network, its IP has changed, or the IP stored in the software no longer matches the one shown on the printer.
  2. Weak Wi-Fi, a distant router or a congested network: the transfer takes too long and times out (Send Failed 55 or 56).
  3. A computer issue: on a Mac the local network permission is missing (Upload Failed 7); the system deleted the temporary sliced file after the software sat idle for a long time (26); or the user name contains Chinese characters when sending over the Internet (1001 or 20008).
  4. An old Creality Print: error 28 appears when the printer takes long to process complex G-code, and newer versions extend the wait from 10 to 60 seconds.
  5. On the K1 series, firmware after 1.3.1.0 asks you to accept a privacy agreement before using the network; or the account signed in on the printer is not the same as in Creality Print.
  6. A company firewall blocking Creality services or, with the Creality WIFI box, an SD card that is missing, full or has errors (Upload Failed 9 or 25).

Checks to tell which one it is

  • Write down the exact number in brackets: each send error code has its cause in Creality's table.
  • On the printer, check under Settings → Network that it is connected and compare its IP with the one shown on the device page in Creality Print.
  • If the software does not show the printer even with its IP, check that the model matching option is enabled on the devices page.
  • From the computer's terminal or Command Prompt, ping the printer's IP for a while: there should be no packet loss and latency is usually below 10 ms.
  • For Creality Cloud, check under the printer's Settings → Account that it is signed in, with the same account you use in Creality Print.

Before you start

Before taking anything apart, cleaning or adjusting it, switch the printer off and unplug it, unless a step says otherwise, and do not touch the nozzle, the heater block or the bed until they have cooled down. If in any doubt about electricity, heat or moving parts, stop and ask a professional.

Step-by-step fix

  1. Reconnect the printer and fix the IP

    Under Settings → Network, connect the printer if it is not connected. If the IP in the software does not match the printer's (or another device uses it), refresh the devices page or remove the printer and add it again with the right IP. If the diagnosis says the network port may be closed, switch the printer off, wait one or two minutes and switch it on again.

    Check: The printer shows online in Creality Print and accepts the job.

    If that does not fix it: Improve the network signal (next step).

  2. Improve the signal (Send Failed 55 or 56)

    Restart the router and network switch, move the printer closer to the router (Creality suggests about 10 metres with no walls in between) and avoid large downloads on the computer while sending. If the file is huge, simplify the model or lower the slicing precision to reduce the G-code, then send it again.

    Check: The ping no longer loses packets and the transfer completes.

    If that does not fix it: Check the specific code in the next steps.

  3. Computer errors (7, 26, 1001 and 20008)

    Upload Failed 7 on a Mac: go to System Settings → Privacy & Security → Local Network and enable Creality Print. Upload Failed 26: copy the model to another folder, slice again and send right after slicing. 1001 or 20008 when sending over the Internet: create an administrator account with a Latin-character user name and slice and send from it.

    Check: The transfer completes without the code.

    If that does not fix it: Update Creality Print (next step).

  4. Update Creality Print (Upload Failed 28)

    Install the latest Creality Print. According to Creality, error 28 happened because the software waited too little for the printer's response with complex G-code (many small segments), and it was fixed in later versions.

    Check: The same file is sent without error.

    If that does not fix it: If you use the Creality WIFI box, check its SD card (next step).

  5. WIFI box: check the SD card (9 and 25)

    Upload Failed 9: insert a valid SD card into the WIFI box. Upload Failed 25: remove the card, copy anything you want to keep, format it as FAT32 on the computer (this erases everything) and put it back.

    Check: The WIFI box receives the file without error.

    If that does not fix it: Contact Creality support with the code and your Creality Print version.

  6. Creality Cloud shows the printer offline

    Let the printer finish its self-check, restart it and make sure the firmware is up to date. On the K1 series, with the printer online, go to Settings → Bind to Creality Cloud and accept the privacy agreement (if «IOT initialization failure» appears, wait a few seconds or switch screens and come back). Choose your region's server and scan the code again with the app.

    Check: The printer shows online in Creality Cloud.

    If that does not fix it: Sign in on the printer with the same account as in Creality Print and bind again.

  7. Company network with a firewall

    If you cannot sign in or use cloud features on a company or restricted network, ask the network administrator to allow the Creality and Creality Cloud domains listed in Creality's guide, with ports 443, 1883 and 80.

    Check: You can sign in and the printer shows online.

    If that does not fix it: Contact Creality support.

Prevention

  • Keep Creality Print and the printer firmware up to date.
  • Send the job right after slicing instead of leaving the software idle for a long time.
  • Place the printer with good Wi-Fi coverage and, if its IP changes, add it again with the correct one.

Still not fixed?

Tell usi3d's AI about your case: choose your printer, describe what you see and add photos if you like. It proposes checks step by step, with their sources.

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Printers it applies to

Creality's FDM printers: CR-10 SE, CR-10 Smart, CR-10 Smart Pro, Ender 3, Ender 3 Pro, Ender 3 S1, Ender 3 S1 Plus, Ender 3 S1 Pro, Ender 3 V2, Ender 3 V3, Ender 3 V3 KE, Ender 3 V3 Plus, Ender 3 V3 SE, Ender 3 V4, Ender 5 Max, Ender 5 S1, Hi, K1, K1 Max, K1 SE, K1C, K2, K2 Plus, K2 Pro, K2 SE, K3 and SPARKX i7.

Official sources

This guide summarises the official documentation linked here:

This guide is general information: usi3d has summarised it from the official documentation linked here, and it may not match your model, its version or its firmware. If in doubt, follow the manual and the support of your printer's manufacturer. You decide what you do with your machine, and working on it may affect its warranty.

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