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Files with the suffix "(1)" arise because Google Drive gets confused, and thinks you have a separate and possibly different copy of that file on your computer, so rather than overwriting, it creates a copy with "(1)" suffix. If you just have a couple of files, delete them and the orginal with no suffix. However, if you have a lot, if you want to be sure, or if it continually creates the "(1)" files, then restart Google Drive:
- Stop Google Drive (right-click over the icon at the bottom right, settings, Quit Google Drive)
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