By the path you provided that looks to be hosted at 1&1.. The shared hosting they provide used to be configured 'PHP as CGI' which has some quirks but I don't think that is related (yet) to your problem..
I think you have a path problem..
The path shown in the error I think is your absolute path on their server, which I don't recall TWG needing as input during configuration..
You should have need for paths like "/" and "/gallery/" etc.. in the configuration though. As I recall your web-root for shared 1&1 hosting is simply "/".
Try making a "test.php" file and paste the code below into it. The info might help you sort out your path problem.
Code:
<?
$path = getcwd();
echo "Script Name : ";
echo $_SERVER['SCRIPT_FILENAME'];
echo "<br><br>Your absolute path is: ";
echo $path;
?>
As for the error itself, it seems to be indicating that
index.inc.php can't find the
showfolders.inc.php file -- probably can't find the other includes that it needs either.
I know this isn't much an answer but I recall having to fiddle with scripts sometimes in order to get them working with 1&1 shared hosting.
The couple suggestions I can think of would be:
- if you tried to manually install the script, try the installer version
or
- if you tried the installer version, try manually installing it
or
- go line by line through your config.php or my_config.php and try things with the path related settings