Unable to download backup from site – 404 error

Backup folder permission are set to 755 on both sites with the issue, and one of the folders contains a .backup_warnings file:

{"php":{"8608b7c7633baa1f6ced9d7a70c8413f":"Undefined variable: disable_supercache_htaccess_warning, \/home\/xxxxxx\/public_html\/wp-content\/plugins\/wp-super-cache\/wp-cache.php, 371","af21e915a99c89e176ee9f05e9fe0a03":"Undefined index: updatehtaccess, \/home\/xxxxx\/public_html\/wp-content\/plugins\/wp-super-cache\/wp-cache.php, 1345","c2a87e3047e1739100171949b1be9d8e":"Undefined index: cache_scheduled_time, \/home\/xxxxxx\/public_html\/wp-content\/plugins\/wp-super-cache\/wp-cache.php, 1620"}}

After force showing hidden files on to other site, I can see a further backup_warnings file. This time related to the Wordfence security plugin

{"php":{"70d5ebb6aa606107dbcf4eaa705260eb":"Undefined index:  domainLookupEnd, \/home\/airuser\/air-8.com\/wp-content\/plugins\/wordfence\/lib\/wordfenceClass.php, 1695","801ab12f7b65a66e332cb2082082518e":"Undefined index:  connectEnd, \/home\/xxxx\/xxxx\/wp-content\/plugins\/wordfence\/lib\/wordfenceClass.php, 1695","1f64d78114b2d25b3230a2585cac748f":"Undefined index:  responseStart, \/home\/xxxx\/xxxx\/wp-content\/plugins\/wordfence\/lib\/wordfenceClass.php, 1695","bccb6796e1908561855cc463949b22ff":"Undefined index:  responseEnd, \/home\/xxxx\/xxxx\/wp-content\/plugins\/wordfence\/lib\/wordfenceClass.php, 1695","af51333c6445910c68c2161afc0a3660":"Undefined index:  domReady, \/home\/xxxx\/xxxx\/wp-content\/plugins\/wordfence\/lib\/wordfenceClass.php, 1695","9e3ecca673dd2da2c1b9a1b9f05a89ef":"Undefined index:  loaded, \/home\/xxxx\/xxxx\/wp-content\/plugins\/wordfence\/lib\/wordfenceClass.php, 1695"}}

Are these BackUpWordpress compatibility issues with the SuperCache and Wordfence plugins or the other way around?

I can’t speak for Wordfence, but BackupWordpress is definitely compatible with the BulletProofSecurity (BPS) plugin.

Thanks for your input Poddy. I did try the BPS plugin a while back, and while it offers excellent security, I prefer Wordfence for the user interface and easy of setting up (and security of course). It’s strange as on another site the combination of Wordfence and BackUpWordpress is functioning fine.

I checked in the wp-content folder and there was a .htaccess file there with the following code:

Order Allow,Deny
Deny from all
<Files ~ "\.(gif|jpe?g|png|css|js|xml)$">
Allow from all
</Files>

I saved a copy of this file before deleting it. After this, I regain the ability to download the backups from the dashboard.