I run "pg_upgrade -xx" fromPostgreSQL8.3 to PostgreSQL9.4.5 on window server 2008. It will show some wrong information:
cannot write to log file pg_upgrade_internal.log
Failure, exiting.
It seems that the upgrade can be successful on window 7. It seems to be a permissions problem. I get some information about restricting privileges from source code, and I find the changes "Run pg_upgrade and pg_resetxlog with restricted privileges on Windows, so that they don't fail when run by an administrator (refer to http://www.postgresql.org/docs/9.4/static/release-9-4-2.html )" for release 9.4.2. Why did you do this? How can I solve this problem? I hope you can help me.
Best Regards,
Leo