File name searches on Windows such as *.epub or fred.* shouldn't need the Windows Indexer - and we should call them 'finds' rather than 'searches'. They use the file system index specified when the device was formatted - for NTFS that's the Master File Table (MFT), for FAT32 it's the File Allocation Table etc.
I suggest you start by disabling the Index service, an internet search for 'disable indexing windows 10' will show you how to do that. if filename finds are still failing then the file system index is probably corrupt, which may be repairable if it's an NTFS device.
BR
|