# Problems in test in fast 8

**URL:** <https://forums.nlr.gov/t/problems-in-test-in-fast-8/1868>\
**Category:** General\
**Created:** [July 2, 2018, 5:18pm UTC](https://forums.nlr.gov/t/problems-in-test-in-fast-8/1868 "2018-07-02T17:18:57Z")\
**Posts on this page:** 1\
**Showing post:** 3

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**Author:** ![Mostafa.Haggag](https://avatars.discourse-cdn.com/v4/letter/m/8e8cbc/32.png) [@Mostafa.Haggag](https://forums.nlr.gov/u/Mostafa.Haggag)\
**Post date:** [July 3, 2018, 6:41am UTC](https://forums.nlr.gov/t/problems-in-test-in-fast-8/1868/3 "2018-07-03T06:41:26Z")

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> [@Jason.Jonkman](#):
>
> Dear Mostafa,
> 
> Your first screenshot is reporting an error about “allocating space”. This error pertains to how much memory (RAM) you have available on your machine. If your model needs more than 2-GB of RAM, you’ll need to use the 64-bit version of the Windows executable rather than the 32-bit version. If you simply don’t have enough RAM on your machine, you’ll need to reduce the memory requirement of the model e.g. by reducing the number of analysis nodes in the structural, aerodynamic, and/or hydrodynamic modules.
> 
> Your second screenshot is reporting an error that an aerodynamic analysis node has fallen below the still water level (SWL). My guess is you have tower aerodynamic nodes set in AeroDyn and your model is heaving downward. You can resolve this error by raising the lowest tower node so that it does not fall below SWL when heaving downward.
> 
> Your third screenshot is cut-off before any errors are reported.
> 
> Best regards,

for my second screenshot, this is the main test files that were downloaded with fast8 I did not change anything in them. are you saying that they came with an error when I downloaded from fast 8 for windows? so this is a kind of an error occurring for everybody if I understood correctly?how do i change in the tower node?is it something in aerodyn tower file ?  
[drive.google.com/open?id=1nkgbr … \_Vo8DFjHZ2](https://drive.google.com/open?id=1nkgbrnqRXUvxffQN3PqYZM_Vo8DFjHZ2)  
this is a link to the files i am using if you want take a look  
thank you so much  
mostafa

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