BEGIN failed--compilation aborted at C:/xampp/perl/site/lib/ModPerl/Const.pm line 18

Problem Description
While starting Apache web server it fails with following error message.

[Tue Jun 19 16:21:17 2012] [error] Attempt to reload DynaLoader.pm aborted.
Compilation failed in require at C:/xampp/perl/site/lib/ModPerl/Const.pm line 18.
BEGIN failed--compilation aborted at C:/xampp/perl/site/lib/ModPerl/Const.pm line 18.
Compilation failed in require at C:/xampp/perl/site/lib/Apache2/Const.pm line 18.
BEGIN failed--compilation aborted at C:/xampp/perl/site/lib/Apache2/Const.pm line 18.
Compilation failed in require at C:/xampp/apache/conf/extra/startup.pl line 9.
BEGIN failed--compilation aborted at C:/xampp/apache/conf/extra/startup.pl line 9.
Compilation failed in require at (eval 2) line 1.

Investigation of the Problem
No other process is listening on port 80. I have manually checked via netstat -aon command as it is stated in http://arjudba.blogspot.com/2009/07/how-to-check-or-identify-which-process.html. Even I manually off the teamviewer, Skype. But nothing happens. Still same problem while starting Apache.

I dig into it further and I found the culprit is Oracle.

Cause of the Problem
I found I was getting this error because PERL5LIB was set. During Oracle installation the environmental variable PERL5LIB was set by Oracle 10g. So the simplest solution is to unset PERL5LIB when starting the Apache web sever. I did this by creating a cmd file that unsets PERL5LIB and runs Apache along with a shortcut for starting it.

By the way Oracle 10g had defined PERL5LIB to:

PERL5LIB=C:\oracle\product\10.2.0\db_1\perl\5.8.3\lib\MSWin32-x86;C:\oracle\product\10.2.0\db_1\perl\5.8.3\lib;C:\oracle\product\10.2.0\db_1\perl\5.8.3\lib\MSWin32-x86;C:\oracle\product\10.2.0\db_1\perl\site\5.8.3;C:\oracle\product\10.2.0\db_1\perl\site\5.8.3\lib;C:\oracle\product\10.2.0\db_1\sysman\admin\scripts;

Solution of the Problem

@c:
@cd \xampp
@set PERL5LIB=
apache_start.bat

Here is the output,

C:\xampp>@c:

C:\xampp>@cd \xampp

C:\xampp>@set PERL5LIB=

C:\xampp>apache_start.bat
Diese Eingabeforderung nicht waehrend des Running beenden
Bitte erst bei einem gewollten Shutdown schliessen
Please close this command only for Shutdown
Apache 2 is starting ...

Here goes the output from Apache logfile,

[Tue Jun 19 16:26:22 2012] [notice] Digest: generating secret for digest authentication ...
[Tue Jun 19 16:26:22 2012] [notice] Digest: done
[Tue Jun 19 16:26:23 2012] [notice] Apache/2.2.21 (Win32) mod_ssl/2.2.21 OpenSSL/1.0.0e PHP/5.3.8 mod_perl/2.0.4 Perl/v5.10.1 configured -- resuming normal operations
[Tue Jun 19 16:26:23 2012] [notice] Server built: Sep 10 2011 11:34:11
[Tue Jun 19 16:26:23 2012] [notice] Parent: Created child process 3604
[Tue Jun 19 16:26:24 2012] [notice] Digest: generating secret for digest authentication ...
[Tue Jun 19 16:26:24 2012] [notice] Digest: done
[Tue Jun 19 16:26:25 2012] [notice] Child 3604: Child process is running
[Tue Jun 19 16:26:25 2012] [notice] Child 3604: Acquired the start mutex.
[Tue Jun 19 16:26:25 2012] [notice] Child 3604: Starting 150 worker threads.
[Tue Jun 19 16:26:25 2012] [notice] Child 3604: Starting thread to listen on port 443.
[Tue Jun 19 16:26:25 2012] [notice] Child 3604: Starting thread to listen on port 443.
[Tue Jun 19 16:26:25 2012] [notice] Child 3604: Starting thread to listen on port 80.
[Tue Jun 19 16:26:25 2012] [notice] Child 3604: Starting thread to listen on port 80.