# Error PDB file cat not exist

**URL:** <https://ask.bioexcel.eu/t/error-pdb-file-cat-not-exist/638>\
**Category:** HADDOCK\
**Created:** [November 25, 2017, 10:32pm UTC](https://ask.bioexcel.eu/t/error-pdb-file-cat-not-exist/638 "2017-11-25T22:32:47Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![shawnteh1711](https://avatars.discourse-cdn.com/v4/letter/s/3da27b/32.png) [@shawnteh1711](https://ask.bioexcel.eu/u/shawnteh1711)\
**Post date:** [November 25, 2017, 10:32pm UTC](https://ask.bioexcel.eu/t/error-pdb-file-cat-not-exist/638/1 "2017-11-25T22:32:47Z")

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The HADDOCK category is meant to discuss any HADDOCK-related issue. For general information about HADDOCK refer to [http://www.bonvinlab.org/software/haddock2.2](http://www.bonvinlab.org/software/haddock2.2)

I am using cygwin under window to do statistical contact analysis for HADDOCK small molecule binding site tutorial. I am doing the setup under tcsh shell.

However when i try to run the command $WDIR/contacts-analysis.csh ‘cat file.nam’ for statistical contact analysis, it show the following error:

ERROR: PDB file cat does not exist  
ERROR: PDB file (null) contains no resiude

![image](https://dub1.discourse-cdn.com/flex013/uploads/bioexcel/original/1X/5113eabcf1a126583acd2b18ecfaacf3caa031c3.png)

Would appreciate if anyone can kindly explain to me what is the problem. Thank you.

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<div class="post-metadata">

**Author:** ![shawnteh1711](https://avatars.discourse-cdn.com/v4/letter/s/3da27b/32.png) [@shawnteh1711](https://ask.bioexcel.eu/u/shawnteh1711)\
**Post date:** [November 26, 2017, 2:37am UTC](https://ask.bioexcel.eu/t/error-pdb-file-cat-not-exist/638/2 "2017-11-26T02:37:52Z")

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I recheck and find out that i am using single quote instead of back quote. Suppose to be no problem now.