# Error on plugin c++

**URL:** <https://community.freefem.org/t/error-on-plugin-c/1445>\
**Category:** General Discussion\
**Created:** [January 18, 2022, 2:46pm UTC](https://community.freefem.org/t/error-on-plugin-c/1445 "2022-01-18T14:46:47Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![larismartins](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/larismartins/32/2712_2.png) [@larismartins](https://community.freefem.org/u/larismartins)\
**Post date:** [January 18, 2022, 2:46pm UTC](https://community.freefem.org/t/error-on-plugin-c/1445/1 "2022-01-18T14:46:47Z")

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Hi, I’m trying to execute the exemple mat\_psi.cpp but I get the following error:

```auto
mat_psi.cpp:30:10: fatal error: ff++.hpp: No such file or directory

```

Can someone help me?

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<div class="post-metadata">

**Author:** ![frederichecht](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/frederichecht/32/15_2.png) [@frederichecht](https://community.freefem.org/u/frederichecht)\
**Post date:** [January 31, 2022, 4:10pm UTC](https://community.freefem.org/t/error-on-plugin-c/1445/2 "2022-01-31T16:10:51Z")

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do you use ff-c++ script to compile ?  
because ff++.hpp is the include dir of plugin/seq  
ls include/ff++.hpp