公司mail突然掛掉無法收信，無法重啟dovecot服務
查詢狀態會出現"dovecot已停止執行但subsys被鎖定"

查maillog檔如下：
May 14 20:22:06 axelite dovecot: Dovecot v1.0.13 starting up
May 14 20:22:06 axelite dovecot: Auth process died too early - shutting down May 14 20:22:06 axelite dovecot: auth(default): dovecot-auth: error while loading shared libraries: libldap.so.2: cannot open shared object file: No such file or directory
May 14 20:22:06 axelite dovecot: ssl-build-param: ssl-build-param:
error while loading shared libraries: libssl.so.4: cannot open shared object file: No such file or directory
May 14 20:22:06 axelite dovecot: child 22796 (ssl-build-param) returned error 127
May 14 20:22:06 axelite dovecot: child 22797 (auth) returned error 127

dovecot已經重裝一樣無法啟動

請問這發生原因為何...要如何解決@@?