"Page not available" when submitting request via NCBIBLastHandler

Mar 17, 2011 at 11:47 PM

Just trying to get into using MBF...  trying to get submission to NCBI BLAST for running BLASTX. but I'm getting a WebException saying the page is not available when SubmitRequest() is called. I'm pretty much using the stock methods that are generated by MBF when creating a new "MBF application" in VS2010, except I'm using "blastx" as the program for the parameters. I'm targeting .net 4 and nothing else in particular seems odd. Just wanted to run a very simple test before trying to build a workflow. Any suggestions? The URIs likely haven't changed at all, but is there an easy way to check what the query string it's trying to send to the server is? I haven't been able to find one so far.


Mar 17, 2011 at 11:51 PM

have you checked with Fiddler how the actual request looks like and what the response is?

Mar 18, 2011 at 11:41 AM


Thanks for showing interest in MBF. We are currently looking into your query and will get back to you shortly.

Support Team

Mar 18, 2011 at 1:48 PM

Thanks for the tip on Fiddler, I didn't know about that before and it looks useful.

Amusingly, without changing anything I came in today and tried it again and now it works. Seems like it was an NCBI service issue, and nothing to do with MBF!

Mar 18, 2011 at 4:03 PM

It looks like this is fixed now, great - but in general service providers don't seem to have the same high standards for webservice availability as they do for the availability of their more conventional websites. If in doubt, you can always try the BLAST services in our BioExcel or WPF-based Sequence Assember demo tools - they use MBF and so if they fail, it is a good indicator the service is down rather than you are using MBF incorrectly.

If you require a more reliable connection to a common service such as BLAST, you could always implement a simple failover from, say, the NCBI BLAST to the EBI BLAST, or vice-versa. We didn't build this directly into MBF, but it wouldn't be too hard to do in any MBF-based application.

Mar 18, 2011 at 5:20 PM

I have used EBI Blast service over the course of 2 years and never had a single service failure but I don't have experience with NCBI so I don't know how reliable their services are.