# Error in starting comfyui, problem with manager and python...python -m pip not available. Falling back to uv **URL:** \ **Category:** Windows\ **Tags:** issue, starting-comfyui\ **Created:** [October 21, 2025, 7:37am UTC](https://forum.comfy.org/t/error-in-starting-comfyui-problem-with-manager-and-python-python-m-pip-not-available-falling-back-to-uv/3881 "2025-10-21T07:37:50Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![DiabolicX](https://yyz1.discourse-cdn.com/flex009/user_avatar/forum.comfy.org/diabolicx/32/783_2.png) [@DiabolicX](https://forum.comfy.org/u/DiabolicX)\ **Post date:** [October 21, 2025, 7:37am UTC](https://forum.comfy.org/t/error-in-starting-comfyui-problem-with-manager-and-python-python-m-pip-not-available-falling-back-to-uv/3881/1 "2025-10-21T07:37:50Z")
I installed 25H2, then I did everything necessary to install the Comfyui program, however, when starting it, I constantly get the same error. I thought this error was due to the new system or a bug in 25H2. I installed other versions of Python several times and the thing keeps happening (i also did a fresh install for comfyui), comfyui does not start and the same error always appears. [ComfyUI-Manager] python -m pip not available. Falling back to uv. [ComfyUI-Manager] Neither python -m pip nor uv are available. Cannot proceed with package operations. Failed to execute startup-script: E:\ComfyUI\_windows\_portable\_nvidia\ComfyUI\_windows\_portable\ComfyUI\custom\_nodes\comfyui-manager\prestartup\_script.py / Neither pip nor uv are available for package management Then I went back to 24H2, first start and everything is fine (too long to open but I was happy that the program started), I install the manager and the start is normal, I even manage to make some pictures! This morning I start the program again and the same error repeats, I really have no idea what else to do, I tried everything I could think of and what I found on the internet