By default, Aspera Sync logs all file system synchronization events and transfers to a log file in the following directory (based on whether you have 32-bit or 64-bit Windows, and which Aspera transfer product is installed on your system):

Aspera Product Location
Enterprise or Connect Server C:\Program Files [(x86)]\Aspera\Enterprise Server\var\log\
Point-to-Point C:\Program Files [(x86)]\Aspera\Point-to-Point\var\log\
Desktop Client C:\Program Files (x86)\Aspera\Client\var\log\
Important: If you attempt to sync a directory without the proper read/write permissions, the directory and files it contains are not marked with an ERROR flag in the file directory status output. However, the error will be noted in the log file.