# Problem installing extension on windows

**URL:** <https://discourse.slicer.org/t/problem-installing-extension-on-windows/2221>\
**Category:** Support\
**Created:** [March 1, 2018, 3:43pm UTC](https://discourse.slicer.org/t/problem-installing-extension-on-windows/2221 "2018-03-01T15:43:38Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Stephen\_Gwilym](https://avatars.discourse-cdn.com/v4/letter/s/b38774/32.png) [@Stephen\_Gwilym](https://discourse.slicer.org/u/Stephen_Gwilym)\
**Post date:** [March 1, 2018, 3:43pm UTC](https://discourse.slicer.org/t/problem-installing-extension-on-windows/2221/1 "2018-03-01T15:43:39Z")

</div>

Operating system: Windows  
Slicer version:4.1.1  
Expected behavior: download occurs  
Actual behavior:  
Error GUI pops up, informing me that " error opening files for writing"  
C:\programfiles\slicer 4.8.1\slicer.exe

If I ‘ignore’ this, the next file in sequence also has an opening error.  
Any advice please?  
Steve

---

<div class="post-metadata">

**Author:** ![jcfr](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/jcfr/32/17825_2.png) [@jcfr](https://discourse.slicer.org/u/jcfr)\
**Post date:** [March 1, 2018, 3:45pm UTC](https://discourse.slicer.org/t/problem-installing-extension-on-windows/2221/2 "2018-03-01T15:45:14Z")

</div>

Hi @Stephen_Gwilym

Thanks for the feedback.

Could you provide the exact step leading to this problem ?

Also, the you indicated you are using Slicer `4.1.1` but the installation path seems to indicate `4.8.1`. Which version are you effectively using ?

---

<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [March 1, 2018, 3:49pm UTC](https://discourse.slicer.org/t/problem-installing-extension-on-windows/2221/3 "2018-03-01T15:49:48Z")

</div>

Make sure you have write access and enough space in you `Extensions installation` folder. You can find its location in menu: Edit / Application settings / Extensions -\> Extensions installation path.