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I understand that you are unable to send a fax from your MS Word as the printer shows as offline.
This issue could occur settings are not correct.
Let's go through a few steps to troubleshoot this issue.
And here's the step by step guide for you listed below:
1. Open the document on your computer that you want to fax.
2. On the File menu in your software application, click Print.
3. From the Name list, select the printer that has “fax” in the name.
4. To change settings (such as selecting to send the document as a black fax or a color fax), click the button that opens the Properties dialog box. Depending on your software application, this button might be called Properties, Options, Printer Setup, Printer, or Preferences.
5. After you have changed any settings, click OK.
6. Click Print or OK.
7. Enter the fax number and other information for the recipient, change any further settings for the fax, and then click Send Fax. The printer begins dialing the fax number and faxing the document.
Note: To use this feature, make sure you have installed the HP printer software on your computer, the printer is connected to a working telephone line, and the fax function is set up and functioning correctly.