If Foxit PDF IFilter does not work for desktop search, there may be several reasons as below.
I. Your IFilter is not a licensed one.
Since Foxit PDF IFilter desktop version has been bundled with Foxit PhantomPDF 5.2 and later version, its license is also controlled by Foxit PhantomPDF.
Please check if IFilter module is included in PhantomPDF license by running Foxit PhantomPDF > HELP > About Foxit PhantomPDF in the ribbon.
II.Foxit PDF IFilter has not been registered to windows system as PDF IFilter.
To check if Foxit PDF IFilter desktop version is correctly registered, please click Start > Control Panel > Indexing Options > Advanced > File Types > navigate to “pdf” and see if its IFilter (Filter Description) is Foxit PDF IFilter.
Click Start > Run > cmd > input the following commands to register Foxit PDF IFilter to Windows.
• Register “PDFFilt_x64.dll” (for 64bit version)
• Register “PDFfilt.dll” (for 32bit version)
III.The folder you want to index has not been added to your indexing.
To check it, please go to Start > Control Panel > Indexing Options > Modify. In the Indexed Locations window, check if the folder you want to index has not been selected. If not, please add it.
Note: If you do not see a directory in Indexing Option > Modify, you may need to make the drive offline accessible. See alsohttp://technet.microsoft.com/en-us/library/cc738531(v=ws.10).aspx.
IV.Windows Search 4.0 has not been installed (For Windows XP).
Click http://www.microsoft.com/download/en/details.aspx?id=23 to download and install Windows Search 4.0 on Windows XP.
V.Indexing Options has not been enabled in your system.
(For Windows XP/Vista/7)
To enable Indexing Options, please go to Start > Control panel > Programs and Features > Turn Windows Features on or off > Indexing Service.