To fix this line, just remove the "my" before "$VARDB_database":

    if ( ($line =~ /^VARDB_database/) && ($CLIDB_database < 1) )
        {$VARDB_database = $line;   my $VARDB_database =~ s/.*=//gi;}
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Using strict and warnings will save you from bugs like the above which fail silently:

use strict;
use warnings;

#path to astguiclient configuration file:
my $PATHconf = '/etc/astguiclient.conf';
my (
$PATHlogs,
$VARserver_ip,
$VARDB_server,
$VARDB_database,
$VARDB_user,
$VARDB_pass,
$VARDB_custom_user,
$VARDB_custom_pass,
$VARDB_port); 

# Now perl knows the variables you will use, so if there is 
# a typo later like "$PATHlog" instead of "$PATHlogs" then 
# perl will tell you how to fix it, instead of just failing 
# silently (like crappy PHP and Python :^)


open(conf, "$PATHconf") || die "can't open $PATHconf: $!\n";
my @conf = <conf>;
close(conf);
my $i=0;
foreach(@conf){
    my $line = $conf[$i];
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