Pokergrapher crashing at startup

[Stargoose]

Hello everyone ...

A friend of mine has trouble getting Pokergrapher working.
Everytime he starts it up, it crashes.

Error message:
<font class="small">Code:</font><hr /><pre>String was not recognized as a valid DateTime</pre><hr />

.NET Framework is installed.

Anyone knows how to make it work ???

Thanks in advance ...