Hi Anne,
In Word, greyed-out Replace buttons usually mean the document can’t be edited right now. Please check the following place:
Documents from email or downloads often open in Protected View, a read-only mode that blocks editing. Look for a yellow bar at the top and click Enable Editing.
If there’s no yellow bar, check the document protection. Go to Review > Restrict Editing and look at the pane on the right. If protection is on, click Stop Protection, which may ask for a password.
Go to File > Info > Protect Document and clear Always Open Read-Only (it may be labelled “Always open view-only”). You can also save a copy and edit that.
If your Microsoft 365 subscription has expired or needs reactivation, Office goes into Reduced Functionality Mode, which disables all editing commands. IRM and admin restrictions can’t be cleared locally, so for those you’d need to check the sensitivity label or permissions applied to the file.
If the rest of the Home tab (Bold, Paste, and so on) is also greyed out, the document is locked and one of the four causes above applies.
If the issue persists after verifying the settings, close Microsoft Word and restart your computer. If the problem continues, perform an Online Repair of your Microsoft Office installation to detect and fix any corrupted program files.
For more information, please consult Repair an Office application | Microsoft Support
If you have any questions or need further assistance, please feel free to share them in the comments on this post.
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