The below works for me and prints all pdfs in a directory (prompts to print each fine in sequence):

* Change the value in m.lcPath below to print all pdfs in the directory
* set the printer other than the example shown below which is for testing only
* This example prompts to print each form - remove the prompt if necessary


CLEAR ALL
CLOSE ALL
RELEASE ALL
CLEAR

*--Next line for test purposes only to select a printer
set PRINTER TO NAME (GETPRINTER())
*--This is the line which determines the directory used
m.lcPath = GETDIR()
IF !DIRECTORY(m.lcPath)
	RETURN
ENDIF


=GoPDF(m.lcPath)
RETURN


FUNCTION GoPDF(qpath)

DO DECLexewait

#DEFINE INFINITE  0xFFFFFFFF
PRIVATE lcStartupInfo, lcProcInfo, hProcess, ;
   lnPrio, lnIBelieve1
lnIBelieve1 = 1   && Don't remember what that was
lnPrio = 32 && Priority of Process=Normal
lcStartupInfo = CHR(68) + REPLI(CHR(0), 67)
lcProcInfo = REPLI(CHR(0), 16)
m.lcApp = "acrord32.exe"
lcresult = Acrofind()
IF !EMPTY(lcresult)
   m.lcApp = lcresult
ENDIF


=ADIR(pdfs,qpath+"*.PDF")
IF TYPE('ALEN(pdfs,1)') = "N"
   FOR I = 1 TO ALEN(pdfs,1)
      m.lccmdline = " /p /h"
      m.lccmdline = m.lccmdline + qpath+pdfs(I,1)
      IF FILE(qpath+pdfs(I,1)) .and. YESNO('Print '+qpath+pdfs(I,1)+'?')
         WAIT WINDOW "Printing "+qpath+pdfs(I,1)+"..." NOWAIT
         =PrintPDF()
      ENDIF
   ENDFOR
ENDIF
WAIT CLEAR
RETURN


FUNCTION PrintPDF
IF CreateProcess(0, m.lcApp+" "+m.lccmdline+CHR(0), 0,0,;
      m.lnIBelieve1, m.lnPrio,;
      0, 0, @lcStartupInfo, @lcProcInfo) <> 0
   hProcess = buf2dword(SUBSTR(lcProcInfo, 1,4))
   hThread = buf2dword(SUBSTR(lcProcInfo, 5,4))
   lncount = 0
   DOEVENTS
   DO WHILE .T.
      exitcode = 0               && initialize return value to 0
      = GetExitCodeProcess(hProcess, @exitcode)   && try to obtain process exit code
      IF exitcode # 259            && not still busy
         EXIT                     && fall out of loop
      ELSE
         lncount = lncount + 1
         IF lncount < 45
            *
         ELSE
            EXIT
         ENDIF
      ENDIF
      = Sleep (100)               && wait .1 seconds
   ENDDO
   = Sleep(1000)
   = SendData('Adobe Reader')
   = CloseHandle(hThread)
   = CloseHandle(hProcess)
ELSE
   =MESSAGEBOX("Unable to initiate AcroRd32.Exe")
ENDIF
RETURN

PROCEDURE DECLexewait
DECLARE INTEGER CreateProcess IN kernel32;
   INTEGER lpAppName, STRING lpCmdLine, INTEGER lpProcAttr,;
   INTEGER lpThrAttr, INTEGER bInhHandles, INTEGER dwCrFlags,;
   INTEGER lpEnvir, INTEGER lpCurDir, ;
   STRING @lpStInfo, STRING @lpProcInfo
DECLARE INTEGER GetLastError IN kernel32
DECLARE INTEGER CloseHandle IN kernel32 INTEGER hObject
DECLARE INTEGER WaitForSingleObject IN kernel32;
   INTEGER hHandle, INTEGER dwMilliseconds
DECLARE INTEGER GetExitCodeProcess IN WIN32API INTEGER hProcess, INTEGER @lpExitCode
DECLARE Sleep IN kernel32 INTEGER dwMilliseconds
RETURN

FUNCTION buf2dword(lcBuffer)
RETURN ASC(SUBSTR(lcBuffer, 1,1)) + ;
   ASC(SUBSTR(lcBuffer, 2,1)) * 256 +;
   ASC(SUBSTR(lcBuffer, 3,1)) * 65536 +;
   ASC(SUBSTR(lcBuffer, 4,1)) * 16777216
RETURN

*--------------
FUNCTION SendData
PARAMETER tcTitle

DECLARE INTEGER FindWindow IN Win32API AS FindWindow STRING, STRING

lnwindow = FindWindow(0,tcTitle)

IF lnwindow > 0
   #DEFINE WM_CLOSE 16
   #DEFINE WM_KEYDOWN  0x0100
   #DEFINE WM_SYSCOMMAND  0x0112
   #DEFINE WM_COMMAND 0x00110818
   #DEFINE WM_KEYUP 0x0101
   #DEFINE WM_SETFOCUS 0x0007

   DECLARE SHORT PostMessage IN user32;
      INTEGER   HWND,;
      INTEGER   Msg,;
      STRING   wParam,;
      INTEGER   LPARAM

   HWND = lnwindow
   ReturnValue = PostMessage(HWND, WM_SETFOCUS, 0, 0)
   ReturnValue = PostMessage(HWND, WM_CLOSE, 0, 0)
   RELEASE oShell
   RETURN .T.
ELSE
   RETURN .F.
ENDIF


*------------------------------------------------------
PROCEDURE CloseApp
PARAMETERS hThread

DECLARE Sleep IN kernel32 INTEGER dwMilliseconds
=Sleep(100)

LOCAL awin_apps, vfp_handle, ln_current_window,ln_window_count
DIMENSION awin_apps[1,2]
vfp_handle=0
DECLARE INTEGER FindWindow ;
   IN win32api ;
   INTEGER nullpointer, ;
   STRING cwindow_name
DECLARE INTEGER GetWindow ;
   IN win32api ;
   INTEGER ncurr_window_handle, ;
   INTEGER ndirection
DECLARE INTEGER GetWindowText ;
   IN win32api ;
   INTEGER n_win_handle, ;
   STRING @ cwindow_title, ;
   INTEGER ntitle_length
ln_current_window = hThread
ln_window_count=0
DO WHILE ln_current_window>0
   lc_window_title=SPACE(255)
   ln_length=GetWindowText(ln_current_window, ;
      @lc_window_title,LEN(lc_window_title))
   IF ln_length>0
      lc_window_title=STRTRAN(TRIM(lc_window_title),CHR(0),"")
   ELSE
      lc_window_title=""
   ENDIF
   IF ln_current_window>0 .AND. !EMPTY(lc_window_title)
      ln_window_count=ln_window_count+1
      DIMENSION awin_apps(ln_window_count,2)
      awin_apps[ln_Window_Count,1]=lc_window_title
      awin_apps[ln_Window_Count,2]=ln_current_window
   ENDIF
   ln_current_window=GetWindow(ln_current_window,2)
ENDDO
PRIVATE it
FOR it = 1 TO ALEN(awin_apps,1)
   IF TYPE('awin_apps(it,1)')="C" .AND. "ADOBE" $ UPPER(awin_apps(it,1))
      IF TYPE('awin_apps(it,2)')="N"
         =close2(awin_apps(it,2))
      ENDIF
   ENDIF
   IF TYPE('awin_apps(it,1)')="C" .AND. "ACROBAT" $ UPPER(awin_apps(it,1))
      IF TYPE('awin_apps(it,2)')="N"
         =close2(awin_apps(it,2))
      ENDIF
   ENDIF
   IF TYPE('awin_apps(it,1)')="C" .AND. "DDE SERVER" $ UPPER(awin_apps(it,1))
      IF TYPE('awin_apps(it,2)')="N"
         =close2(awin_apps(it,2))
      ENDIF
   ENDIF
ENDFOR

RETURN .T.

*----------------------------------------------------------
PROCEDURE close2
PARAMETERS HWND
#DEFINE WM_CLOSE 16
#DEFINE WM_SETFOCUS 0x0007
#DEFINE WM_USER       0x0400
#DEFINE kMsg_Save 1235

DECLARE SHORT PostMessage IN user32;
   INTEGER   HWND,;
   INTEGER   Msg,;
   STRING   wParam,;
   INTEGER   LPARAM
DECLARE INTEGER SetForegroundWindow IN Win32API;
   INTEGER HWND
DECLARE INTEGER SetActiveWindow IN Win32API;
   INTEGER HWND

=PostMessage(HWND, WM_SETFOCUS, 0, 0)
=PostMessage(HWND, WM_CLOSE, 0, 0)

RETURN .T.


*--------------
FUNCTION SendN
PARAMETER lnwindow

IF lnwindow > 0
   #DEFINE WM_KEYDOWN  0x0100
   #DEFINE WM_SYSCOMMAND  0x0112
   #DEFINE WM_COMMAND 0x00110818
   #DEFINE WM_KEYUP 0x0101
   #DEFINE WM_SETFOCUS 0x0007

   DECLARE SHORT PostMessage IN user32;
      INTEGER   HWND,;
      INTEGER   Msg,;
      STRING   wParam,;
      INTEGER   LPARAM

   HWND = lnwindow
   ReturnValue = PostMessage(HWND, WM_SETFOCUS, 0, 0)
   oShell = CREATEOBJECT("wscript.shell")
   oShell.Sendkeys("N")
   RELEASE oShell
   RETURN .T.
ELSE
   RETURN .F.
ENDIF

*----------------------------------------------------------------------
FUNCTION Acrofind
PRIVATE WNetGetConnection, lpszLocalname, lpszRemoteName, ;
   sLen, Lni, DRIVE, Dtype, llfound, Lni
PRIVATE ARRAY afilesfound(1,3)
DIMENSION afilesfound(1,3)
afilesfound(1,1)=" "
llfound = .F.
Lni = 0
DECLARE INTEGER WNetGetConnection IN win32api ;
   STRING lpszLocalName,;
   STRING lpszRemoteName,;
   INTEGER @ lpchBuffer && Declare the external WNetGetConnection ;
   API FUNCTION
slpRemoteName = SPACE(254) && Initialize variables
sLen = LEN(slpRemoteName) && Initialize variables
*--Populate the one dimensional array with valid drive letters
FOR I = 1 TO 26 && Loop through drive letters A thru Z
   DRIVE = CHR(I + 64)
   Dtype = DRIVETYPE(DRIVE) && Determine drive type
   DO CASE
      CASE Dtype = 3 && Hard drives
         Lni=Lni+1
         DIMENSION adrivelist(Lni,3)
         adrivelist(Lni,1)=DRIVE
         adrivelist(Lni,2)=.F.
         adrivelist(Lni,3)=.F.
      CASE Dtype = 4 && Removable or network drives
         iSuccess = WNetGetConnection(DRIVE + ;
            ":",@slpRemoteName,@sLen)
         IF iSuccess = 0
            Lni=Lni+1
            DIMENSION adrivelist(Lni,3)
            adrivelist(Lni,1)=DRIVE
            adrivelist(Lni,2)=.F.
            adrivelist(Lni,3)=.F.
         ENDIF
   ENDCASE
ENDFOR
llfound = .F.
FOR Lni = 1 TO ALEN(adrivelist,1)
   FOR ib = 10 TO 1 STEP -1
      lcacrofile = adrivelist(Lni,1)+":"+"\Program Files\Adobe\Acrobat "+ALLTRIM(STR(ib))+".0\Reader\AcroRd32.Exe"
      IF FILE(lcacrofile)
         llfound = .T.
         EXIT
      ENDIF
   ENDFOR
   IF llfound
      EXIT
   ENDIF
ENDFOR

CLEAR DLLS WNetGetConnection

IF llfound
   RETURN lcacrofile
ELSE
   RETURN ''
ENDIF

*----------------------------------------------------------------------
FUNCTION YESNO
LPARAMETER mmessage, mscheme, mtimeout, mtitle, myesno, mssgtop

IF EMPTY(mmessage)
   mmessage = "Unknown Question."
ENDIF

IF EMPTY(mscheme)
   mscheme = 7
ENDIF

IF EMPTY(mtimeout)
   mtimeout = 0
ENDIF

IF EMPTY(mtitle)
   mtitle = _SCREEN.CAPTION
ENDIF

IF EMPTY(myesno)
   myesno = 0
ENDIF

IF ";" $ mmessage
   mmessage = STRTRAN(mmessage, ';', ' ')
ENDIF

IF myesno = 0
   IF mtimeout > 0
      lnResult = MESSAGEBOX(mmessage, 36+4096, mtitle, mtimeout * 1000)
   ELSE
      lnResult = MESSAGEBOX(mmessage, 36+4096, mtitle)
   ENDIF
ELSE
   IF mtimeout > 0
      lnResult = MESSAGEBOX(mmessage, 292+4096, mtitle, mtimeout * 1000)
   ELSE
      lnResult = MESSAGEBOX(mmessage, 292+4096, mtitle)
   ENDIF
ENDIF

DO CASE
   CASE lnResult = -1        && TimeOut
      IF myesno = 0
         lcChoice = "YES"
      ELSE
         lcChoice = "NO"
      ENDIF
   CASE lnResult = 1         && Ok
      lcChoice = "OK"
   CASE lnResult = 2         && Cancel
      lcChoice = "CANCEL"
   CASE lnResult = 3         && Abort
      lcChoice = "ABORT"
   CASE lnResult = 4         && Retry
      lcChoice = "RETRY"
   CASE lnResult = 5         && Ignore
      lcChoice = "IGNORE"
   CASE lnResult = 6         && Yes
      lcChoice = "YES"
   CASE lnResult = 7         && No
      lcChoice = "NO"
   OTHERWISE
      lcChoice = "ESCAPE"
ENDCASE

RETURN lcChoice = 'YES'