- Server operating system version
- Windows Server 2022
- Plesk version and microupdate number
- Plesk Obsidian 18.0.70 Update #3 Web Host Edition
Hi,
We’re facing a migration failure during conversion of Classic app pools to Integrated mode, matching the issue described here: Failed to allow applications in Classic to work in Integrated mode after migration in web.config files
Migration Scenario:
I'm running a migration using Plesk Migrator:
Debug Messages:
Diagnostics:
Is there an updated patch or fix for this migrator issue (potential regression PMT‑5599)?
Thanks,
We’re facing a migration failure during conversion of Classic app pools to Integrated mode, matching the issue described here: Failed to allow applications in Classic to work in Integrated mode after migration in web.config files
Migration Scenario:
I'm running a migration using Plesk Migrator:
- Source Server: Windows Server 2012
- Target Server: Windows Server 2022
Failed to allow applications in Classic to work in Integrated mode after migration in web.config files
Migration tools tried to perform operation in 3 attempts: 'utf-8' codec can't decode byte 0xff in position 57: invalid start byte
Debug Messages:
2025-08-05 15:17:43 Exception
Exception:
Traceback (most recent call last):
File "C:\Program Files (x86)\Plesk\admin\plib\modules\panel-migrator\backend\lib\python\parallels\core\safe.py", line 191, in try_subscription_with_rerun
func()
File "C:\Program Files (x86)\Plesk\admin\plib\modules\panel-migrator\backend\lib\python\parallels\core\workflow\runner\by_subscription.py", line 526, in <lambda>
lambda: action.run(self._context, subscription),
File "C:\Program Files (x86)\Plesk\admin\plib\modules\panel-migrator\backend\lib\python\parallels\core\actions\fix_web_config_integrated_mode.py", line 134, in run
runner.execute_command(
File "C:\Program Files (x86)\Plesk\admin\plib\modules\panel-migrator\backend\lib\python\parallels\core\runners\base.py", line 131, in execute_command
str_decode(execution_results.stdout, output_encoding),
File "C:\Program Files (x86)\Plesk\admin\plib\modules\panel-migrator\backend\lib\python\parallels\core\utils\common\string_utils.py", line 119, in str_decode
return s.decode(encoding)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xa0 in position 57: invalid start byte
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Program Files (x86)\Plesk\admin\plib\modules\panel-migrator\backend\lib\python\parallels\core\safe.py", line 164, in try_subscription
yield
File "C:\Program Files (x86)\Plesk\admin\plib\modules\panel-migrator\backend\lib\python\parallels\core\safe.py", line 197, in try_subscription_with_rerun
raise MultipleAttemptsMigrationError(exceptions)
parallels.core.safe.MultipleAttemptsMigrationError: Migration tools tried to perform operation in 3 attempts: 'utf-8' codec can't decode byte 0xa0 in position 57: invalid start byte
2025-08-05 15:17:43 Error
Failed to perform an action on subscription 'example.com': Failed to allow applications in Classic to work in Integrated mode after migration in web.config files Exception message: Migration tools tried to perform operation in 3 attempts: 'utf-8' codec can't decode byte 0xa0 in position 57: invalid start byte
Diagnostics:
- Verified web.config file is UTF-8 encoded (no BOM).
- Inspected the flagged line, no unusual characters found.
- Hex-level analysis confirmed no invalid bytes at the reported offset.
Is there an updated patch or fix for this migrator issue (potential regression PMT‑5599)?
Thanks,