failed to TAR up repositories

Hi,

some days ago I set up a new Virtual Host in Virtualmin. Nearly all features are enabled, including git repositories.

After that I entered my home directory in the shell, renamed public_html to public_html_ and created a new, empty public html directory. In this directory I cloned a git repository which is hosted on github.com. Files should be integer.

So far, my application works fine but every night, when backing up my server, I encounter the following problem, which is sent to me by mail:

[...] Backing up Git repositories and configuration files .. .. failed to TAR up repositories : [...]

With the result, that my Server is backup up only partially.

Unfortunately googling the error "failed to TAR up repositories" ends up in 0 usable results.

What I did: I checked out (cloned) the Github-Repository a second time, which did not help. I removed the whole public_html directory with the git-files for one night, but still the error. I tared the public_html - directory manually (tar czfv public_html.tgz public_html) that brings no error.

What can I do?

Thank you very much in advance,

Matthias