[MacPorts] #71408: xmlcatmgr @2.2_1: Image error: /opt/local/bin/xmlcatmgr already exists and does not belong to a registered port.

[MacPorts]

#71408: xmlcatmgr @2.2_1: Image error: /opt/local/bin/xmlcatmgr already exists and
does not belong to a registered port.
-----------------------------------------+-------------------------------
  Reporter:  thetrial                    |      Owner:  (none)
      Type:  defect                      |     Status:  new
  Priority:  Normal                      |  Milestone:
 Component:  ports                       |    Version:  2.10.5
Resolution:                              |   Keywords:  legacy-os, sierra
      Port:  xmlcatmgr, docbook-xml-4.2  |
-----------------------------------------+-------------------------------

Comment (by ryandesign):

 Such a message is not usually caused by a MacPorts bug but by a problem on
 your computer. The message means a file MacPorts wants to install is
 already there and MacPorts does not have a record of having installed it;
 you would need to figure out why it exists on your computer if it didn't
 come from MacPorts.

 One somewhat common way for this to happen is if you ran a third-party
 software installer that was itself built with MacPorts in its default
 prefix of /opt/local. Files installed by such an installer would not be
 known to your MacPorts install and would even overwrite any files your
 MacPorts had already installed. You could use `ls -l
 /opt/local/bin/xmlcatmgr` to see when the file was modified, which is
 probably when it was installed; maybe that reminds you of a software
 installer that you ran at that time. Cleaning up from such a mess can be
 tricky. Easiest is probably to uninstall the third-party software (if they
 provide an uninstall method),
 [https://guide.macports.org/#installing.macports.uninstalling remove all
 traces of MacPorts including unknown files in /opt/local], and then
 reinstall MacPorts and the ports you want. Also request that the
 distributors of the third-party installer withdraw all installers they
 built that install into /opt/local and to rebuild their installers with
 their copy of MacPorts built from source in a different prefix specific to
 their software.

 Other causes of the message are possible but less likely. For example, if
 you manually created the file /opt/local/bin/xmlcatmgr it would cause this
 message, but I imagine you probably wouldn't do that. Or you might've used
 MacPorts to install the xmlcatmgr port and then MacPorts lost track of the
 fact that it had installed it, for example if its registry database were
 corrupted or removed.

-- 
Ticket URL: <https://trac.macports.org/ticket/71408#comment:1>
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