Originally Posted by
pschlute
If you go to edit/catalog settings, it will show the path where the catalog files are stored. On my windows computer this is the default C drive.
My photos are stored on a different computer drive. LR is quite happy to have the catalog and photos on different drives.
Possibly what is happening to you is that the path for the catalog is specified as the external drive. if your computer goes to sleep then the external drive is no longer seen by the computer, and therefore LR.