File runs\train\switch\weights\last.pt cannot be opened.

[zengmanying]

python train.py --workers 8 --device 0 --batch-size 2 --data data/coco.yaml --img 320 --cfg cfg/training/yolov7.yaml --hyp data/hyp.scratch.p5.yaml --weights "" --epochs 1200
YOLOR 2025-2-18 torch 2.4.1+cu118 CUDA:0 (NVIDIA GeForce RTX 3060 Laptop GPU, 6143.5MB)

(yolov7_new) D:\github\yolov7-main>pip list
Package Version

---

absl-py 2.2.2
asttokens 3.0.0
backcall 0.2.0
cachetools 5.5.2
certifi 2025.1.31
charset-normalizer 3.4.1
colorama 0.4.6
contourpy 1.1.1
cycler 0.12.1
decorator 5.2.1
executing 2.2.0
filelock 3.16.1
fonttools 4.57.0
fsspec 2025.3.0
google-auth 2.39.0
google-auth-oauthlib 1.0.0
grpcio 1.70.0
idna 3.10
importlib_metadata 8.5.0
importlib_resources 6.4.5
ipython 8.12.3
jedi 0.19.2
Jinja2 3.1.6
kiwisolver 1.4.7
Markdown 3.7
MarkupSafe 2.1.5
matplotlib 3.7.5
matplotlib-inline 0.1.7
mpmath 1.3.0
networkx 3.1
numpy 1.23.5
oauthlib 3.2.2
opencv-python 4.11.0.86
packaging 24.2
pandas 2.0.3
parso 0.8.4
pickleshare 0.7.5
pillow 10.4.0
pip 24.2
prompt_toolkit 3.0.51
protobuf 4.21.2
psutil 7.0.0
pure_eval 0.2.3
pyasn1 0.6.1
pyasn1_modules 0.4.2
Pygments 2.19.1
pyparsing 3.1.4
python-dateutil 2.9.0.post0
pytz 2025.2
PyYAML 6.0.2
requests 2.32.3
requests-oauthlib 2.0.0
rsa 4.9.1
scipy 1.10.1
seaborn 0.13.2
setuptools 75.1.0
six 1.17.0
stack-data 0.6.3
sympy 1.13.3
tensorboard 2.14.0
tensorboard-data-server 0.7.2
thop 0.1.1.post2209072238
torch 2.4.1+cu118
torchaudio 2.4.1+cu118
torchvision 0.19.1+cu118
tqdm 4.67.1
traitlets 5.14.3
typing_extensions 4.13.2
tzdata 2025.2
urllib3 2.2.3
wcwidth 0.2.13
Werkzeug 3.0.6
wheel 0.44.0
zipp 3.20.2

error info:
Traceback (most recent call last):
File "train.py", line 617, in
train(hyp, opt, device, tb_writer)
File "train.py", line 465, in train
torch.save(ckpt, last)
File "C:\Users\78527.conda\envs\yolov7_new\lib\site-packages\torch\serialization.py", line 651, in save
with _open_zipfile_writer(f) as opened_zipfile:
File "C:\Users\78527.conda\envs\yolov7_new\lib\site-packages\torch\serialization.py", line 525, in _open_zipfile_writer
return container(name_or_buffer)
File "C:\Users\78527.conda\envs\yolov7_new\lib\site-packages\torch\serialization.py", line 496, in init
super().init(torch._C.PyTorchFileWriter(self.name))
RuntimeError: File runs\train\switch\weights\last.pt cannot be opened.