PHP Internal Error file_exists

When operating from a terminal connected as a network drive in Windows 10, the following error is output.

Error PHP file_exists(): open_basedir restriction in effect. File(/NEXTCLOUD-SERVER/data/ACCOUNT/files/FOLDER/SAMPLE.eps/desktop.ini) is not within the allowed path(s): (/MY-SERVER/:/tmp/:/dev/urandom) at /NEXTCLOUD-SERVER/lib/private/Files/Storage/Local.php#173

When opening files directly from nextcloud, there seems to be no problem on Windows side. It seems that preservation is done without problem.
Is this a problem with the setting of the Nextcloud server?

This does not happen reliably every time. It happens from time to time. And this also occurred in nc12.0.2.

Nextcloud version (eg, 10.0.2): 12.0.3
Operating system and version (eg, Ubuntu 16.04): CentOS 7.3
Apache or nginx version (eg, Apache 2.4.25): nginx 1.11.13
PHP version (eg, 5.6): 7.1.9

This problem has not been solved even in version 12.0.4.
If I use WebDAV on Windows 10, can not I avoid this?