I need help !! : What is my problem?

[Eric Piollet]

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After my login in horde :

When i want to go to IMP I have :=20

Warning: Undefined variable: horde in =
/etc/httpd/htdocs/horde/imp/index.php on line 20

Warning: Cannot add header information - headers already sent by (output =
started at /etc/httpd/htdocs/horde/imp/index.php:20) in =
/etc/httpd/htdocs/horde/imp/index.php on line 28

What is the problem?

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