Action 2017-05-29 16:28:09 ------- Create qrecallBackup
Action 2017-05-29 16:28:09 archive: /Volumes/Seagate Backup Plus Drive/qrecallBackup.quanta
Action 2017-05-29 16:28:09 Failure Create failed
Action 2017-05-29 16:28:09 A network or disk error was encountered.
Action 2017-05-29 16:28:09 ------- Create incomplete (00:00)
QRecall 2017-05-29 16:28:09 Failure Create command failed
QRecall 2017-05-29 16:28:09 cannot create repository package
QRecall 2017-05-29 16:28:09 Error: You don?t have permission.
QRecall 2017-05-29 16:28:09 Name: qrecallBackup.quanta
QRecall 2017-05-29 16:28:09 Description: You don?t have permission to save the file ?qrecallBackup.quanta? in the folder ?Seagate Backup Plus Drive?.
QRecall 2017-05-29 16:28:09 Failure cannot create repository package
QRecall 2017-05-29 16:28:09 Error: You don?t have permission.
QRecall 2017-05-29 16:28:09 Name: qrecallBackup.quanta
QRecall 2017-05-29 16:28:09 Description: You don?t have permission to save the file ?qrecallBackup.quanta? in the folder ?Seagate Backup Plus Drive?.

QRecall is telling you that you (or specifically, your user account) doesn't have permission to create/write a document in the root directory of that volume.

A QRecall archive is much like any document: you must have read, write, and execute permission in the directory you want to create it.

There are a couple of easy ways to accomplish this:

Ignore ownership

If you plan to use the entire volume for backup, it might be easier to simply turn off permissions and ownership for that volume. Select the volume in the Finder, choose Get Info, and check the "Ignore ownership" option. Once you do this, macOS will let you read and write anything on the volume.

Fix the permissions

Change the ownerships and/or permissions of the directory you want to use. If you can't change the root directory, create a sub folder and make yourself its owner. Note that any other computers/users that require access the same archive will also need appropriate permissions. (This is why the "ignore ownership" option is the simplest.)

Final note: while QRecall makes every effort to support all major filesystems for hosting archives, it's happiest (and most efficient) when your archive volume is formatted for macOS. Many external drives ship pre-formatted for Windows, so a quick erase in Disk Utility can improve your performance and reliability.