Whether I install the software or delete the software, it will happen! Please take a look.

Whether I install the software or delete the software, it will happen! Please take a look at the Linux general technology-Linux technology and application information. The following is a detailed description. Whether to install software on a terminal or uninstall software. There will be the following situations.
Excuse me!
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Reading the package list... complete
Analyzing the dependency tree of the software package
Reading status information... complete
The following software packages will be [uninstalled ]:
Gdb
0 software packages have been upgraded, 0 new software packages have been installed, 1 software package has to be uninstalled, and 0 software packages have not been upgraded.
Two software packages are not fully installed or uninstalled.
After decompression, the space is 4 kb and kb.
Do you want to continue? [Y/n] y
(Reading the database... the system currently has 230087 files and directories installed .)
Uninstalling gdb...
Processing the trigger for man-db...
Setting postfix (2.7.1-1ubuntu0. 2 )...

Postfix configuration was untouched. If you need to make changes, edit
/Etc/postfix/main. cf (and others) as needed. To view Postfix configuration
Values, see postconf (1 ).

After modifying main. cf, be sure to run'/etc/init. d/postfix reload '.

Running newaliases
Newaliases: warning: valid_hostname: invalid character 231 (decimal ):??????
Newaliases: fatal: file/etc/postfix/main. cf: parameter myhostname: bad parameter value :??????
Dpkg: An error occurred while processing postfix (-- configure:
The sub-process has installed the post-installation script, and the error code 75 is returned.
Dpkg: the configuration of mailutils cannot be continued due to dependency issues:
Mailutils depends on default-mta | mail-transport-agent; however:
The software package "default-mta" is not installed ".
The software package postfix provides default-mta, but it is not yet configured.
The software package "mail-transport-agent" is not installed ".
The software package postfix provides mail-transport-agent, but it has not been configured yet.
Dpkg: An error occurred while processing mailutils (-- configure:
Dependency problem-Not Configured
Processing the trigger for libc-bin...
The error message indicates that this is an error caused by the previous problem and has not been written to the apport report.
Ldconfig deferred processing now taking place
An error occurred during processing:
Postfix
Mailutils
E: Sub-process/usr/bin/dpkg returned an error code (1)
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