I have the same problems with Zotero. I can't get the toolbar back after attempting a few troubleshooting methods. Does creating new user account really help?
I tried the following steps, I found that the Zotero.dotm is unchecked on my Word. Then, I tick it. But after I restart my Word, it is unticked again...
Check if the Zotero plugin is correctly installed
Open the Templates and Add-ins window by going to File → Options → Add-ins, selecting “Word Add-ins” in the Manage drop-down at the bottom, and clicking “Go…”. Make sure Zotero.dotm is present and ticked
There are other steps that you don't say you've followed, so you'll want to be sure you've tried them.
Beyond that, I'm afraid there's not really anything else we can suggest — this would be some sort of problem in your Word installation, not a problem with the plugin. If this is an institutional computer, you should ask your IT department. Otherwise, you can try reinstalling Word.
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I have the same problems with Zotero. I can't get the toolbar back after attempting a few troubleshooting methods. Does creating new user account really help?
See https://www.zotero.org/support/word_processor_plugin_troubleshooting#zotero_tab_does_not_appear_in_the_word_ribbon, and if you're still having trouble, let us know everything you tried and what happened at each step.
I tried the following steps, I found that the Zotero.dotm is unchecked on my Word. Then, I tick it. But after I restart my Word, it is unticked again...
Check if the Zotero plugin is correctly installed
Open the Templates and Add-ins window by going to File → Options → Add-ins, selecting “Word Add-ins” in the Manage drop-down at the bottom, and clicking “Go…”.
Make sure Zotero.dotm is present and ticked
Beyond that, I'm afraid there's not really anything else we can suggest — this would be some sort of problem in your Word installation, not a problem with the plugin. If this is an institutional computer, you should ask your IT department. Otherwise, you can try reinstalling Word.