New comfyui，SeedVR2 can't work now! who know how to fix it?

[woyomo8]

upgrade comfyui 0.17 0.18 ,seedvr2 can't work . who know how to fix it?

[naxci1]

You need to check the logs; attach all the logs here. I'm using the old Comfyui, and when I tested it with the new one on SeedVR2, the speed was slower, so the old one is better.

[breatkan250]

@naxci1 I noticed that too. Which ComfyUI version is the fastest and most stable for SeedVR2?

[breatkan250]

also, is there a way to run flash_attn 3 or sageattn_3 for Windows 11 ComfyUI?

[naxci1]

#540

[DarthDiabolik]

It also stopped working for me today, I reinstalled, updated, uninstalled, installed the old version and nothing, it still shows as if it is not installed

[naxci1]

Hi @DarthDiabolik

You need to attach the entire log.

[Sulqwerty]

[2026-03-25 06:23:18.064] Traceback (most recent call last):
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\utils\import_utils.py", line 953, in get_module
return importlib.import_module("." + module_name, self.name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "importlib_init.py", line 126, in import_module
File "", line 1204, in _gcd_import
File "", line 1176, in _find_and_load
File "", line 1147, in _find_and_load_unlocked
File "", line 690, in _load_unlocked
File "", line 940, in exec_module
File "", line 241, in _call_with_frames_removed
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\loaders\peft.py", line 39, in
from .lora_base import fetch_state_dict, func_optionally_disable_offloading
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\loaders\lora_base.py", line 56, in
from peft.tuners.tuners_utils import BaseTunerLayer
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\peft_init.py", line 17, in
from .auto import (
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\peft\auto.py", line 32, in
from .peft_model import (
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\peft\peft_model.py", line 37, in
from transformers import Cache, DynamicCache, EncoderDecoderCache, HybridCache, PreTrainedModel
ImportError: cannot import name 'HybridCache' from 'transformers' (E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\transformers_init.py)

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
File "E:\ComfyUI_py3.11.9\ComfyUI\nodes.py", line 2227, in load_custom_node
module_spec.loader.exec_module(module)
File "", line 940, in exec_module
File "", line 241, in call_with_frames_removed
File "E:\ComfyUI_py3.11.9\ComfyUI\custom_nodes\seedvr2_videoupscaler_init.py", line 7, in
from .src.interfaces import comfy_entrypoint, SeedVR2Extension
File "E:\ComfyUI_py3.11.9\ComfyUI\custom_nodes\seedvr2_videoupscaler\src\interfaces_init_.py", line 8, in
from .video_upscaler import SeedVR2VideoUpscaler
File "E:\ComfyUI_py3.11.9\ComfyUI\custom_nodes\seedvr2_videoupscaler\src\interfaces\video_upscaler.py", line 10, in
from ..utils.downloads import download_weight
File "E:\ComfyUI_py3.11.9\ComfyUI\custom_nodes\seedvr2_videoupscaler\src\utils\downloads.py", line 14, in
from .model_registry import MODEL_REGISTRY, DEFAULT_VAE
File "E:\ComfyUI_py3.11.9\ComfyUI\custom_nodes\seedvr2_videoupscaler\src\utils\model_registry.py", line 14, in
from ..models.video_vae_v3.modules.attn_video_vae import VideoAutoencoderKLWrapper
File "E:\ComfyUI_py3.11.9\ComfyUI\custom_nodes\seedvr2_videoupscaler\src\models\video_vae_v3\modules\attn_video_vae.py", line 20, in
from diffusers.models.autoencoders.vae import DecoderOutput, DiagonalGaussianDistribution
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\autoencoders_init_.py", line 1, in
from .autoencoder_asym_kl import AsymmetricAutoencoderKL
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\autoencoders\autoencoder_asym_kl.py", line 23, in
from .vae import DecoderOutput, DiagonalGaussianDistribution, Encoder, MaskConditionDecoder
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\autoencoders\vae.py", line 25, in
from ..unets.unet_2d_blocks import (
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\unets_init_.py", line 6, in
from .unet_2d import UNet2DModel
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\unets\unet_2d.py", line 24, in
from .unet_2d_blocks import UNetMidBlock2D, get_down_block, get_up_block
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\unets\unet_2d_blocks.py", line 36, in
from ..transformers.dual_transformer_2d import DualTransformer2DModel
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\transformers_init_.py", line 5, in
from .auraflow_transformer_2d import AuraFlowTransformer2DModel
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\models\transformers\auraflow_transformer_2d.py", line 23, in
from ...loaders import FromOriginalModelMixin, PeftAdapterMixin
File "", line 1229, in _handle_fromlist
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\utils\import_utils.py", line 943, in getattr
module = self._get_module(self._class_to_module[name])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\diffusers\utils\import_utils.py", line 955, in get_module
raise RuntimeError(
RuntimeError: Failed to import diffusers.loaders.peft because of the following error (look up to see its traceback):
cannot import name 'HybridCache' from 'transformers' (E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\transformers_init.py)

[2026-03-25 06:23:18.064] Cannot import E:\ComfyUI_py3.11.9\ComfyUI\custom_nodes\seedvr2_videoupscaler module for custom nodes: Failed to import diffusers.loaders.peft because of the following error (look up to see its traceback):
cannot import name 'HybridCache' from 'transformers' (E:\ComfyUI_py3.11.9\python_embeded\Lib\site-packages\transformers_init_.py)

[naxci1]

I wanted the full log, from start to finish of comfyui, because there must be a SeedVR2 installation error there.

[naxci1]

Gemini says there are a lot of installation issues, so you need to resolve any installation problems with an AI; the AI ​​will tell you what and how to install it.

The error occurs because your peft and diffusers libraries are trying to call a function (HybridCache) that was only recently added to the transformers library. Since you are using an embedded Python environment, it likely contains an older version of transformers that doesn't recognize this command.

Solution Steps
To fix this, you need to force-update the core libraries within your specific ComfyUI environment:

1. Run the Update Command
Open your Command Prompt (CMD) and paste the following line. This targets your specific embedded Python to ensure the correct environment is updated:

Bash
E:\ComfyUI_py3.11.9\python_embeded\python.exe -m pip install --upgrade transformers peft diffusers accelerate
2. Verify the Update
After the installation finishes, you can verify that you are on a compatible version by running:

Bash
E:\ComfyUI_py3.11.9\python_embeded\python.exe -m pip show transformers
The version should ideally be 4.36.0 or higher to support HybridCache.

3. Clear Cache and Restart
Sometimes Python retains old file references in memory. Completely close the ComfyUI terminal window and restart run_nvidia_gpu.bat.

Why this happened
The seedvr2_videoupscaler node uses the diffusers backend. When diffusers imports peft (Parameter-Efficient Fine-Tuning), peft looks for HybridCache inside transformers. If transformers is outdated, the entire loading chain breaks, preventing the custom node from appearing in your menu.

[DarthDiabolik]

Hi @DarthDiabolik

You need to attach the entire log.

I'm sorry, but last night I completely deleted SeedVR2 (I had to because I had it installed in most of my workflows, so that message warning me that SeedVR2 was not installed was already starting to annoy me), so the entire log won't help now. I've tried a million different options suggested by the AI ​​and none of them worked. Grok told me that this problem has been around for a while, but that there have been a lot more questions about it in the last few days.

[naxci1]

The problem with ComfyUI is that if you install too many nodes, it can corrupt the others. That's why I only install 3 nodes and no more. The same goes for PIP packages; you shouldn't install unnecessary packages or issue commands without knowing what they are, otherwise you'll waste time trying to fix it. My suggestion is to install ComfyUI from scratch and only install SeedVR2. The repository explains how to install it, or you can install it from ComfyUI Manager.

[AlexYez]

replace custom_nodes\seedvr2_videoupscaler\src\optimization\compatibility.py with this fixed code, It will work with transformers 5.x: https://justpaste.it/j8ola