In this blog post, you’ll learn more about the Sybase Error Unable to open backup log ‘%1’ and the reason for receiving this error
Sybase SQL Error Message
Unable to open backup log ‘%1’
Reason for this Error
The server was unable to open the backup log to record the execution of a BACKUP or RESTORE statement. Check the settings of the environment variables used to locate the backup log file. The directory to contain the log must already exist.