Catalog largely gray with "!"

[riskybiscuit33]

I need a pro to help me sort my catalogs. I have SO MANY CATALOGS all merged into one: 145,000 photos...but they mostly show as grayed and !. 

Help!? <email removed for privacy>

Thanks. 

[dj_paige]

When the photos have an exclamation point icon, this means that Lightroom Classic can't find them, the photos are not where Lightroom Classic thinks they should be. So you have to tell Lightroom Classic where they are. This is all explained, with screen captures, in this document.