# Trouble installing q2-perc-norm **URL:** https://forum.qiime2.org/t/trouble-installing-q2-perc-norm/9173 **Category:** Library Support **Created:** [April 8, 2019, 3:56pm UTC](https://forum.qiime2.org/t/trouble-installing-q2-perc-norm/9173 "2019-04-08T15:56:23Z") **Posts on this page:** 1 **Showing post:** 4
### Author: ![ebolyen](https://forum.qiime2.org/user_avatar/forum.qiime2.org/ebolyen/32/11_2.png) [@ebolyen](https://forum.qiime2.org/u/ebolyen) #### Post date: [April 23, 2019, 4:56pm UTC](https://forum.qiime2.org/t/trouble-installing-q2-perc-norm/9173/4 "2019-04-23T16:56:22Z")
Hi @prince and @cduvallet, I think I know whats going on, although I'm surprised conda didn't error. First just to get our ducks in a row, run: ```auto qiime dev refresh-cache ``` (This shouldn't matter, because it automatically detects new versions and re-runs itself as needed, but if everything was working as expected we'd see perc-norm in the list...) * * * What I think may have happened is the conda build for q2-perc-norm uses Python 3.5. As of 2019.1 we [switched to Python 3.6](https://forum.qiime2.org/t/new-year-new-python-3-6/8096), this means existing conda packages should be rebuilt for 3.6 (or built as no-arch). We haven't made any changes to the plugin API, so q2-perc-norm should still work with the latest QIIME 2 version just fine. What we could do is perform a source installation instead which won't have the issue with Python 3.5 vs 3.6 If the source installation doesn't work, then something much stranger is happening. --- _[View the full topic](https://forum.qiime2.org/t/trouble-installing-q2-perc-norm/9173)._