When i've started troubleshooting, i suddenly found a lot of warnings and errors in parsing component, such as:
Error parsing document 'https://<filename>.xlsx'. There is no format handler able to parse documents of the format 'encoffmetro'.
I have no idea what is encoffmetro, and firstly checked my parsing options with Get-SPEnterpriseSearchFileFormat -SearchApplication $ssa
And I found that almost all of my crawled file types have UseIFilter option enabled. Though i've never set this manually and never install third party Ifilters!
Get-SPEnterpriseSearchFileFormat -SearchApplication $ssa | ? {$_.UseIFilter -eq $True} returns me a lot of results, almost all of my file types.
According to https://technet.microsoft.com/en-us/library/jj730455.aspx, UseIFilter are False by default. But I have "True", though i don't have any third-party Ifilters installed!
But what is real trouble, I can't disable this IFilter and return to built-in Ifilter!
I've tried to use: Set-SPEnterpriseSearchFileFormatState -SearchApplication $ssa xlsx -Enable:$True -UseIFilter:$False (or shortly: Set-SPEnterpriseSearchFileFormatState -SearchApplication $ssa xlsx $True $False)
That gives me a reminder to restart Search Host Controller Service. But when i use Get-SPEnterpriseSearchFileFormat anew, got UseIFilter=True again. Even after restarting service.
How can change this? Or how can i reset all file types options to Sharepoint defaults?