Migration tools tried to perform operation in 3 attempts: [Error 3] The system cannot find the path specified:

Symptoms

• Plesk migration fails with the following error:

  PLESK_ERROR: Migration tools tried to perform operation in 3 attempts:
  [Error 3] The system cannot find the path specified: ‘C:Inetpubvhostsexample.comhttpdocswordpress20170217unusedbefore-upgrade-to-3.8wp-contentcachepage_enhancedwww.example.net200910some-long-string-with-alot-of-symbols-in-it-with-some-timestamp/*.*’

• The following error can be found in %plesk_dir%varmodulespanel-migratorsessions<MIGRATION_TIMESTAMP>debug.log:

  Start adjust database connection settings in configuration files of subscription
   ... 
   =|2018-12-16_18:19:13,635|D|ST1|core.safe|example.com|| File "C:Program Files (x86)Pleskadminplibmodulespanel-migratorbackendlibpythonparallelscoreutilsfile_utils.py", line 23, in get_dir_tree 
   =|2018-12-16_18:19:13,635|D|ST1|core.safe|example.com|| for item in os.listdir(path): 
   =|2018-12-16_18:19:13,635|D|ST1|core.safe|example.com||WindowsError: [Error 3] The system cannot find the path specified: 'C:Inetpubvhostsexample.comhttpdocswordpress20170217unusedbefore-upgrade-to-3.8wp-contentcachepage_enhancedwww.example.net200910some-long-string-with-alot-of-symbols-in-it-with-some-timestamp/*.*'

Cause

The error is produced due to a long path (>255 symbols).
This is known bug PMT-3684 which is planned to be fixed in future Plesk updates.

Resolution

In general, this error is about failed adjusting. It is an additional functionality of Plesk Migrator. It just tries fixing connection strings and obsolete paths in *.config files.

As a workaround,

• Connect to the source server via RDP and shorten the path.
• Otherwise, connect to the target server via RDP after migration, review and fix(if necessary) connection strings and obsolete paths in *.config files manually.