# PYNQ v2.5 build failed for zedboard

**URL:** <https://discuss.pynq.io/t/pynq-v2-5-build-failed-for-zedboard/7044>\
**Category:** Support\
**Created:** [May 23, 2024, 6:29am UTC](https://discuss.pynq.io/t/pynq-v2-5-build-failed-for-zedboard/7044 "2024-05-23T06:29:44Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![coco\_latte](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/coco_latte/32/5898_2.png) [@coco\_latte](https://discuss.pynq.io/u/coco_latte)\
**Post date:** [May 23, 2024, 6:29am UTC](https://discuss.pynq.io/t/pynq-v2-5-build-failed-for-zedboard/7044/1 "2024-05-23T06:29:44Z")

</div>

I used Ubuntu18.04 + Vivado 2019.1 + Petalinux2019.1 to build PYNQ v2.5 SD image for Zedboard followed instruction - [PYNQ-2.4 for Zedboard v2018.3](https://discuss.pynq.io/t/pynq-2-4-for-zedboard-v2018-3/2697)  
but I got errors when building SD card image:

Err:1 http ://ports.ubuntu.com/ubuntu-ports bionic InRelease  
The following signatures couldn’t be verified because the public key is not available: NO\_PUBKEY 3B4FE6ACC0B21F32  
Reading package lists… Done  
W: GPG error: http ://ports.ubuntu.com/ubuntu-ports bionic InRelease: The following signatures couldn’t be verified because the public key is not available: NO\_PUBKEY 3B4FE6ACC0B21F32  
E: The repository ‘http ://ports.ubuntu.com/ubuntu-ports bionic InRelease’ is not signed.  
N: Updating from such a repository can’t be done securely, and is therefore disabled by default.  
N: See apt-secure(8) manpage for repository creation and user configuration details.  
apt update failed. Exit value: 100  
Makefile:322: recipe for target ‘/opt/Xilinx/Documents/PYNQ-2.5/sdbuild/build/bionic.arm.stage1.img’ failed  
make: \*\*\* [/opt/Xilinx/Documents/PYNQ-2.5/sdbuild/build/bionic.arm.stage1.img] Error 25

I checked my network, added public key of [ports.ubuntu.com](http://ports.ubuntu.com), and tried many times, but didn’t work. Anyone can help me? 😭