当我这样做时sudo apt-get install...，我遇到如下错误：
Setting up xmail (1.27-1.2) ...
ln: failed to create symbolic link '/var/lib/xmail/aliasdomain.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/aliases.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/ctrl.ipmap.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/ctrlaccounts.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/domains.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/extaliases.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/filters.in.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/filters.out.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/filters.post-data.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/filters.post-rcpt.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/filters.pre-data.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/finger.ipmap.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/mailusers.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/pop3.ipmap.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/pop3links.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/server.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/smtp.ipmap.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/smtp.ipprop.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/smtpauth.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/smtpextauth.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/smtpfwd.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/smtpgw.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/smtprelay.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/spam-address.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/spammers.tab': File exists
ln: failed to create symbolic link '/var/lib/xmail/userdef.tab': File exists
dpkg: error processing package xmail (--configure):
subprocess installed post-installation script returned error exit status 1
E: Sub-process /usr/bin/dpkg returned an error code (1)
有谁能告诉我为什么吗？非常感谢！
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