Reserved characters in filenames?

Question: What are the reserved characters we have to be aware of when naming folders? Answer: It depends on the operating system and filesystem-type of the computer. For example, in Windows, open Windows Explorer, select any file, press F2 to change the filename, and then try to insert a ‘?’ into the filename. You’ll see a tooltip with the set […]

Understanding FTP (a collection of useful links)

The File Transfer Protocol (FTP) and Your Firewall / Network Address Translation (NAT) Router / Load-Balancing Router Wikipedia: File Transfer Protocol Active FTP vs. Passive FTP, a Definitive Explanation The FTP2.DetermineSettings Method Issue when an FTP Server is behind a NAT Router FTP Blockers – TCP/IP Port Filtering and Anti-Virus Deep Inspection Firewalls and Passive FTP (also known as Stateful […]

FTP case sensitivity

Question: I had a question regarding the ChangeRemoteDir method, however. Is it case sensitive? If so, is there any way to force the method to ignore the case and just check for the correct spelling? Also, do I have to call ChangeRemoteDir for each folder level or can I, for example, call ChangeRemoteDir(“folder1/folder2/folder3”)? Answer: The case sensitivity depends on the […]

Equivalent HTML Form and Chilkat HTTP POST

Any HTML form POST can be duplicated programmatically with the Chilkat HTTP component. As an example, consider this HTML: <html> <body> <form name=”input” action=”” method=”post”> Arg1: <input type=”text” name=”arg1″> <br>(Arg2 is a hidden input)<br> <input type=”hidden” name=”arg2″ value=”abc123″> Arg3 <input type=”text” name=”arg3″> <input type=”submit” value=”Submit”> </form> </body> </html> It submits a POST to The ASP that receives the post […]

Message-ID and ReplyToMessageID

Question: Reading through the documentation I don’t see access to the Message-ID. 1. Is it possible to set the Message-ID to string value? ( like a GUID string value ) 2. After a read-confirmation/reply, is there a property to access the ‘ReplyToMessageId’ value? Answer: The GetHeaderField and AddHeaderField methods may be used to set or access any header field.  The […]

421 #4.4.5 Too many connections from your host

Question: I get this error from my SMTP server: 421 #4.4.5 Too many connections from your host What does it mean? Answer: The “too many connections from your host” error is the text of the error message that is coming back from the SMTP server. It indicates that the SMTP server has a limit on how many simultaneous open connections […]

-ERR Mailbox Locked

If you see this error when trying to login to a POP3 server, it most likely means that the server is only allowing a single connection (i.e. session) at a time for each mailbox, and than another user already has mailbox open.  It could also mean that the POP3 administrator temporarily locked the mailbox to prevent access.

Chilkat v8.6.0.0 New Features

Chilkat v8.6.0.0 is being released today. Here’s a list of the major new features/fixes. Documentation and new examples will appear soon after the new version is available at Zip: ZIP64 extensions are now supported. There is effectively no limitation on the size of individual files that can be zipped or unzipped. There is also no limitation for the total […]


This usually happens when trying to use the Chilkat 32-bit .NET 2.0 Assembly on a 64-bit system. Download and use the x64 build for the Chilkat .NET 2.0 Framework at Also, it’s likely that your development environment is 32-bit. You should add a reference to the 32-bit ChilkatDotNet2.dll, but deploy the 64-bit ChilkatDotNet2.dll to the x64 computer. Make sure […]