Customer is trying to use Log Reader on striped backup file. Log Reader does not support striped backups. It will allow you to enter only one backup file.
Workaround - Beginning with LiteSpeed version 6.5 there is a feature called SLSRECAST. The SLSRecast utility (slsrecastx32.exe or slsrecastx64.exe) allows you to convert one LiteSpeed backup into another LiteSpeed backup through the command line, optionally changing encryption, compression, retention and other settings.
Use SLSRECAST to recast the striped Backup file to a single file, then use Log Reader as intended.
Please review solution 88785 for more information and explanation on SLSRECAST.