I tried your command, it can't be worked.
Here are the results.
D:\sratoolkit.2.4.2-1-win64\bin>fastq-dump D:\SRRdata\SRR029692.sra
2014-10-28T11:48:03 fastq-dump.2.4.2 err: data insufficient while constructing header within virtual database module - failed /D/SRRdata/SRR029692.sra
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An error occurred during processing.
A report was generated into the file 'C:\Users\acer/ncbi_error_report.xml'.
If the problem persists, you may consider sending the file
to 'sra@ncbi.nlm.nih.gov' for assistance.
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