Could it be that the default setting for one or more tools is set to use the layer you are trying to delete?
It could also be that some of your favourites may be set to use this layer.
Unfortunately you will have to check each section, elevation, detail, worksheet, layout individually if you want to find where the elements are.
However if you open the Attribute Manager and look at the layers you will see a tick next to those that have been used (or is set as the default layer for a tool).
It still won't tell you any info as to where an element might be or what tool is using that layer.
If there is no tick they should be safe to delete.
Just to be safe always keep a copy of you file before you start deleting bits out - just in case you delete something you shouldn't have.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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