tdg

if you see an error message from tdg itself (i.e. a box with an animated exclamation mark and a description of an error), then you'll be pleased to know that your problem is easy to resolve; simply follow the instructions returned by tdg. If tdg doesn't return an error message then the program itself probably isn't running... this indicates a server problem (but nothing serious)

ensure that you have uploaded all tdg files as ASCII file-types, NOT as binaries (only applies to those users who have used the FTP service to copy their tdg files on to a remote web-server)

check the first line of each ".pl" file... it should include the complete (physical) path to the Perl interpreter on your web-server (your System Administrator or ISP should be able to help with this). Note: this is not required for Microsoft Windows NT servers running IIS (Internet Information Server) so you can leave this line unchanged (do not delete it though). Note: This does not apply to "tdg_library.pl"

check that your web-server has a complete and working Perl version 5.6+ installation (your System Administrator or ISP should be able to help with this)

ensure that all the modules and libraries required by tdg are properly installed and in Perl's search path. The libraries and modules that tdg requires are: "LWP::Simple", "Socket", "GDBM_File" and "CGI.pm" (your System Administrator or ISP should be able to help with this)

check the file permissions, all ".pl" files must be executable (refer to "Installing tdg" for more detailed documentation). Some servers do not allow you to adjust file permissions via FTP, consult your System Administrator (or ISP) for help with this

Microsoft Windows NT / IIS (and other web-servers) require that file-types are "mapped" to a specific application (when there is an application dependency). That is, the web-server needs to be told that files with an extension of ".pl" (for example) should be run by Perl (or whatever application a particular file-type is dependent on). Some System Administrators configure their servers so that only files with a ".plx" extension run via the Perl interpreter. Rename all ".pl" files with "*.plx" suffix to rectify this or consult your System Administrator (or ISP). If you do this, remember to adjust your link so that it calls "tdg_view.plx", not "tdg_view.pl". You could also try renaming the Perl files with a ".cgi" extension

certain Microsoft Windows NT / IIS installations won't work with tdg unless it sends an "OK" header before anything else... edit all the ".pl" files so that the line which reads: # print "HTTP/1.0 200 OK\n"; does not have the "# " at the beginning of the line, save and upload to implement this

search through the "tdg Support Forum" to see if your particular problem has been discussed (and solved) there. If it hasn't - post a message, giving as much detail as possible about the error/problem you have encountered and the configuration of your web-server and Perl installation. We're automatically notified of posts to the forum and we'll endeavour to come up with a solution as quickly as possible after any posting. Other tdg users may also respond with help and advice