I have a word file with many tables with grey background, how can I delete background of all tables at the same time without deleting background for each table?

You would need to use VBA code to do that, but even that would need to process each table in turn.

Your first task is to identify whether the tables have a background, or whether the cells have shading.

Each of the tables would have a Table Style applied to it. IF the same table style was applied to every table then it is possible to modify the Table Style attributes to remove all table backgrounds in one step.

However, the table style's background settings could be overridden locally by:
1. Particular table style conditions (like odd/even rows being turned on and those settings have a background shading)
2. Local cell shading applied.

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Andrew Lockton
Chrysalis Design, Melbourne Australia