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Sometimes it is necessary to add attributes to blocks after many instances of the blocks have already been inserted into the drawing. In this case the new attributes are not automatically added to the prior insertions. The Sync Attributes button will add the new attributes to the older blocks.

The values for these newly synced attributes within the older blocks will be the default value you assign to the attribute when you create it and it will blank if no value is assigned. For blank attributes you will have to select the existing blocks and assign values to those attributes.

Extracting Block Attributes

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