Frequently Asked Question:

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How do I unlock Quick PDF Library with my license key?

To unlock Quick PDF Library so that it is not limited in anyway you need to use the UnlockKey function with your commercial or trial license key after you have initiated the library.

The UnlockKey function returns a value to indicate whether or not the library could be unlocked:

0 = The library could not be unlocked
1 = The library was unlocked successfully

When using the UnlockKey it's always a good idea to check the return value of this function so that you know whether your application is going to work correctly or not. For example:

Dim ClassName
Dim LicenseKey
Dim FileName 

ClassName = "QuickPDFAX0718.PDFLibrary"
LicenseKey = "..." // INSERT LICENSE KEY HERE
FileName = "C:\Hello-World-From-QPL.pdf" 

Dim QP
Dim Result 

Set QP = CreateObject(ClassName)
Result = QP.UnlockKey(LicenseKey) 

If Result = 1 Then 
   MsgBox "Library version: " + QP.LibraryVersion
   MsgBox (QP.LicenseInfo)    Call QP.DrawText(100, 500, "Hello world from Visual Basic 6") 

   If QP.SaveToFile(FileName) = 1 Then 
     MsgBox "File " + FileName + " written successfully." 
   Else 
     MsgBox "Error, file could not be written." 
   End If 

Else 
   MsgBox "Invalid license key. Please set a valid license key." 
End If 

Set QP = Nothing 

If the library is not successfully unlocked then you will run into various problems which will mean your application won't work correctly. So again, it's important to check the return value of the UnlockKey function!