It's just possibly related to one of these two things:

1. Check that your Library Preferences File search option is set to "Deep".

2. Make sure you do not have duplicate texture files in any of your connected libraries.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)