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ncbi-blast-2.3.0+ blastn problem

Hello,

I recently tried installing BLAST+ command line on windows and tried running a blastn command in command prompt

blastn -query test_query.txt -db refseq_rna.00 -out test_output.txt

giving the following error:

Error: NCBI C++ Exception:
TO "..\..\..\..\..\src\corelib\ncbiobj.cpp", line 977: Critical: ncbi::CObject::ThrowNullPointerException() - Attempt to access NULL pointer.

Can anyone please help me on this? Thanks.

blastn ncbi blast-plus windows

Hi! I still cant resolve this problem :( I am using 64-bit windows 8 machine. I installed ncbi-blast-2.3.0+-win64.exe and even re-installed it twice. I followed everything in this tutorial http://www.ncbi.nlm.nih.gov/books/NBK52637/

I have no idea where is the problem. Can anyone please help me ? :( thanks in advance.

It could be a bug in the latest version of blastn. Have you tried contacting their helpdesk ?
In the meantime, make sure that your test_query.txt is properly FASTA-formatted.

1 answer

Not sure if relevant but try removing the zeros from refseq_rna.00

blastn -query test_query.txt -db refseq_rna -out test_output.txt

You do not need to specify the index for the database

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