blender 4.1 to unreal 5.3.2 not working

Hi, Im Carlos and Im new to unreal and blender, I’ve recently been trying to use the Official Send to Unreal addon that was created by the Unreal team so I can easily move assets from Blender to UE5.

Unfortunately though, every time I try to export to Unreal by hitting “push assets” I get a huge error I quote:

Python: Traceback (most recent call last):
File “C:\Users\Carlos Henrique\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\send2ue\operators.py”, line 71, in modal
raise error
File “C:\Users\Carlos Henrique\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\send2ue\operators.py”, line 61, in modal
function(*args, **kwargs)
File “C:\Users\Carlos Henrique\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\send2ue\core\export.py”, line 224, in export_mesh
utilities.select_asset_collisions(asset_name, properties)
File “C:\Users\Carlos Henrique\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\send2ue\core\utilities.py”, line 950, in select_asset_collisions
for mesh_object in get_asset_collisions(asset_name, properties):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “C:\Users\Carlos Henrique\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\send2ue\core\utilities.py”, line 636, in get_asset_collisions
if is_collision_of(asset_name, mesh_object.name, properties):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “C:\Users\Carlos Henrique\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\send2ue\core\utilities.py”, line 832, in is_collision_of
) or re.fullmatch(
^^^^^^^^^^^^^
File “C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\re_init_.py”, line 171, in fullmatch
return compile(pattern, flags).fullmatch(string)
^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\re_init
.py", line 294, in _compile
p = _compiler.compile(pattern, flags)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\re_compiler.py”, line 745, in compile
p = _parser.parse(p, flags)
^^^^^^^^^^^^^^^^^^^^^^^
File “C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\re_parser.py”, line 989, in parse
p = _parse_sub(source, state, flags & SRE_FLAG_VERBOSE, 0)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\re_parser.py”, line 464, in _parse_sub
itemsappend(_parse(source, state, verbose, nested + 1,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File “C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\re_parser.py”, line 850, in _parse
raise source.error('global flags not at the start ’
re.error: global flags not at the start of the expression at position 19

Following the start up guide by the unreal team and various other posts on reddit and other forums I have:

  • Enabled the “Python editor script plugin” in Unreal

  • Enabled the “Editor script plugin” in Unreal

  • Enabled “remote execution” under the python settings in Unreal

  • I have also even set the multicast bind cast address to [0.0.0.0] in Unreal

The addon still seems to give the same message, and I’m not sure what else I can do??

The error message you are experiencing with the “Send to Unreal” addon from Blender seems to be related to a regular expression issue within Python, specifically, the use of global flags. This error might be occurring due to an incompatibility or a bug within the addon’s scripts that handle regex processing.

1. Check Blender and Addon Versions

  • Ensure that you are using a version of Blender that is compatible with the “Send to Unreal” addon. Sometimes, these addons are sensitive to the Blender version due to changes in the API or Python version.
  • Check if there are updates available for the “Send to Unreal” addon that might have addressed this issue.

2. Review Regex Implementation

  • The error re.error: global flags not at the start of the expression suggests that there might be a misuse of regex syntax in the addon’s code. Unfortunately, without modifying the addon’s source code, there’s not much you can do here directly. However, knowing this might help when seeking support from the addon developers.

3. Seek Support and Report Bug

  • Since this seems to be a bug within the addon, consider reporting this issue on the addon’s official support or community forum. Providing them with the detailed error message and your setup might help them identify and resolve the issue in a future update.

4. Temporary Workaround

  • If you are familiar with Python and comfortable making changes to the addon scripts, you might attempt to look into the files mentioned in the error (utilities.py, re_parser.py) and see if the regex expressions can be adjusted. The issue is likely with how flags are used in the regex patterns.
  • Specifically, Python’s re library requires that any global flags (like re.IGNORECASE, re.MULTILINE) be placed at the very start of the pattern. Check if this is being adhered to in the code.

5. Ensure Correct Configuration in Unreal Engine

  • Double-check all settings in Unreal Engine that are required by the addon:
    • Ensure that the plugins and settings like “Remote Execution” are not only enabled but correctly configured.
    • Confirm the IP address and ports settings are correct and there aren’t any firewalls or security settings on your system that might be blocking the connection between Blender and Unreal.

6. Alternative Asset Transfer Methods

  • While you troubleshoot this issue, consider using alternative methods to transfer assets from Blender to Unreal Engine, such as exporting to FBX and importing manually into Unreal. This isn’t as streamlined but can be a reliable stopgap.

Hope this helps.

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