** Using WeBWorK **

Based on the specific error that you posted check the permissions of /opt/webwork/courses/Math1503_Fall_2022/templates/linear_algebra.  Use "ls -l /opt/webwork/courses/Math1503_Fall_2022/templates/" and check that its owner and group are that of your server, and that it has read permission.  The permission should be something like drwxr-xr-x if it is a directory, -rw-r--r-- if it is a regular file, and lrwxrwxrwx if it is a symbolic link.  The are possible variants depending on the owner and group settings that would work.  Just compare the permission for the linear_algebra file, directory, or link to the other files in templates.

You can probably fix permissions for all files in that course by running "sudo chown -R www-data:www-data /opt/webwork/courses/Math1503_Fall_2022" and "sudo chmod -R ug+w /opt/webwork/courses/Math1503_Fall_2022".  This assumes that your server user is www-data.

Another possibility is that a course archive for that course already exists, and the permissions on the file are such that the server can not overwrite it.  Check the contents of /opt/webwork/courses for a file by the name of Math1503_Fall_2022.tar.gz, and check its permissions and ownership.

Note that when a course is archived the html temporary directory is deleted.  Then the next time you try to archive it, you get that the directory is missing.  That has been that way for a long time (but will no longer be that way for WW 2.18).