The SharePoint item being crawled returned an error when requesting data from the web service.

When using FAST search for SharePoint 2010 (F4SP) to crawl a content source that contains managed metadata in the field you might get this error

The SharePoint item being crawled returned an error when requesting data from the web service. ( Error from SharePoint site: *** Index was outside the bounds of the array. )

this is because one or more metadata field is filled with incorrect value. When you open it up it show something like this.

The red underline text means there's no term "Knowledge" in the Knowledge Themes metadata field.

if you leave this red text save in your item properties and run a crawling. You will get this error.

To solve this error

That's simple, correct the red underlined text in metadata field. then FAST search will crawl this item correctly.

Enable Fast Search feature on SharePoint Publishing Site

Refer to
http://social.technet.microsoft.com/Forums/en-US/fastsharepoint/thread/d83894e3-fc7c-40e4-99ab-7ac1a5392265

I got the solution to enable FAST search site template for Publishing site with just one command

Enable-SPFeature –Id SearchExtensions –url

Hope this helps

Clear-FASTSearchContentCollection : Failed to communicate with the WCF service.

According to this title error when clear fast search index using PowerShell command.
Clear-FASTSearchContentCollection -Name sp
and I got this error
Failed to communicate with the WCF service.
then i changed user account to run this command by Shift + Right Click on FAST Search

Then log on as FAST service account to run this command instead of current account.

Hope this helps.

Unable To Process Create Message

http://danmyhre.wordpress.com/2011/02/12/error-unable-to-process-create-message/

http://support.microsoft.com/kb/2290443

FAST Post Configuration Wizard fail

There're many error while you are installing FAST Search for SharePoint. Some of them are in the following links.
I got another error while running the post configuration with 2 server 1 admin and 1 non-admin with 1 row and 2 column.
I tried many times but fail.

But finally I got a simple solution:
Restart server after you install FAST for SharePoint binary then run FAST Configuration wizard again then it works!!

http://pornjeds.blogspot.com/2011/08/installation-of-fast-search-server.html

http://pornjeds.blogspot.com/2011/08/fast-search-server-2010-configuration.html

http://pornjeds.blogspot.com/2011/05/filed-to-initialize-session-with.html

Microsoft FAST Search Administration – Unexpected error occurred while communicating with Administration Service

http://gavinmckay.wordpress.com/2010/09/13/microsoft-fast-search-administration-unexpected-error-occurred-while-communicating-with-administration-service/

Installation of FAST Search Server fails on multi-core system

I've installed FAST Search for SharePoint 2010 on a new 32 core server after running Post Set Up Configuration Wizard I got an error.

finally, I've found this article.
http://support.microsoft.com/kb/2449600

FAST Search Server 2010 Configuration Wizard–“Database Validation Failed: Could not connect to the database. Check the database connection string, the database name and the port number to the database server”.

While your are running FAST Search Configuration Wizard. One thing may happen refer from this post.
http://jamesemann.wordpress.com/2011/07/20/fast-search-server-2010-configuration-wizarddatabase-validation-failed-could-not-connect-to-the-database-check-the-database-connection-string-the-database-name-and-the-port-number-to/

but enable user permission only dbcreator is enough.

Filed to initialize session with document engine: Unable to resolve Contentdistributor

Error Message in event viewer
Failed to connect to servername.domain.com:13391 Failed to initialize session with document engine: Unable to resolve Contentdistributor.

I got this error log several times. One is from Office Web Apps installation.
I installed FAST for SharePoint before deploying OWA. after that i got this error.
the other one I think it occurs after FAST and SharePoint Server were migrated to a new server using vMotion.

Solution.
Just reinstall FAST Certificate into SharePoint Server again follow the step in the below link.
Configure SSL enabled communication

then restart both FAST and SharePoint server.

Cheers