I have just tried the solution kindly proposed by you, DStilman, but the problem persists even when the Zotero window is as wide as my screen is. I first tried on a laptop screen and then on a larger external screen. I can still not see the item pane on the right side (and if am not mistaken I cannot therefore add tags to new entries, either, while the existing tags show and I can add tags to entries that already have tags). Thank you for any additional advice anyone may be able to offer.
Thanks for that. Point is that Standard mode button does not work. So cannot get into Standard mode. No computer settings were altered since Zotero was working fine in 32 bit version. I should have left it there!!!! Awaiting new solutions please.
This has nothing to do with 32-bit vs. 64-bit. Starting in Zotero 7, if the window isn't wide enough, it will automatically switch into Stacked mode, and the Standard/Stacked options in View → Layout will be disabled. If you think that's not working properly, answer my question about your screen resolution and provide a screenshot that shows how wide your window is and the View menu with the options disabled.
OK. I adjusted the size of text etc in Scale and Layout in Display settings from 175% to 125%. Now Standard button in Zotero works, 3rd pane is on RHS not below. Thanks to those who advised.
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I have just tried the solution kindly proposed by you, DStilman, but the problem persists even when the Zotero window is as wide as my screen is. I first tried on a laptop screen and then on a larger external screen. I can still not see the item pane on the right side (and if am not mistaken I cannot therefore add tags to new entries, either, while the existing tags show and I can add tags to entries that already have tags). Thank you for any additional advice anyone may be able to offer.
Functionality is identical whether you're in Standard or Stacked mode.
No computer settings were altered since Zotero was working fine in 32 bit version. I should have left it there!!!!
Awaiting new solutions please.
Now Standard button in Zotero works, 3rd pane is on RHS not below.
Thanks to those who advised.