A: Yes. In fact, you can start with a mail server sample project and extend it to satisfy your security or functionality requirements.
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A: Yes, HTTPS is perfect for transferring a file securely.
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A: One major one. Each TCP connection is created and managed on the thread that created the Server control, so this is not a good choice if you need each connection to be managed on separate threads. For you C++ developers building multi-threaded applications, we recommend the Winsock Tool.
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A: Unfortunately, there is no consistent model for 3rd party component support across Office products and versions. The recommended usage in Excel is to use the product as a reference rather than inserting it as a control. Also, if the spreadsheet ever had a PowerTCP control inserted at any previous time, that data was cached by Excel and a new spreadsheet will be required. When deploying to users, please refer to "Distribution under Internet Information Server" in the documentation for instructions as the technique is the same.
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A: Microsoft Windows XP SP2 is a large update to the Windows XP operating system. The focus of this update is to tighten system security. One of those features is the built-in firewall. By default, Microsoft will turn on the firewall and block all applications from communicating over the Internet. As most PowerTCP products are designed for building Internet applications, those applications may be blocked from accessing the network. The solution to this problem, as it is for any application that needs to access the network, is to grant permission using Microsoft’s configuration utility. Instructions on using the Microsoft firewall are at http://www.microsoft.com/windowsxp/using/security/internet/sp2_wfintro.mspx, and more information about manual network security configuration is available by reading Microsoft Knowledge Base Article - 842242 . Also, Microsoft will disallow using ActiveX controls in Internet Explorer by default. It your web application uses PowerTCP ActiveX controls in IE, your users will have to manually adjust their security settings to allow ActiveX usage. If you find any other problems with SP2 and PowerTCP products, please contact Dart support at support@dart.com.
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A: There is a known bug in the .NET Framework that prevents ActiveX components from being licensed properly when they are dynamically instantiated. Currently, the workaround is to place the control on a form and instantiate an instance of that form without actually showing it. Microsoft is aware of the problem and we are currently looking at other workarounds for the problem.
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A: The following error has been experienced by some customers:

"The referenced component could not be found. Invalid Primitive Type: System.Reflection.Missing. Only CLS compliant primitive types can be used. Consider using CodeObjectCreateExpression."

SP3 for Framework 1.0 and SP1 for Framework 1.1 broke compatibility with some ActiveX controls. You need to download a hotfix from Microsoft.

Anyone you distribute your app to will also have to run this hotfix until Microsoft releases SP4 for Framework 1.0 and SP2 for Framework 1.1

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A: Our implementation requires that a certificate be properly imported into a valid Microsoft Certificate Store. If you are importing a certificate that was created from a non-MS source (such as OpenSSL), please be sure that you export the certificate properly before attempting to import it into an MS Cert store. Check the docs for whatever SSL system you are using for this info. Also, make sure that when you export your certificate, regardless of your SSL library, that it includes the private key. A certificate that is exported without a private key can not be used as a valid certificate when imported into the Microsoft Certificate Store.
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A: The problem is that a runtime license needs to be provided for the control. Resolution: Get LPK_TOOL.EXE from Microsoft. You can find it in their Cabinet Development kit. It is also on one of the CDs that comes with Visual Studio. Use the LPK_TOOL to create an .lpk file for YOUR control. We can't stress YOUR control enough. In other words, let's say that you have a control called MyControl that contains several Dart controls. When choosing the control in the LPK_TOOL listbox, choose MyControl, NOT the Dart Controls. Again, we can't stress this part enough as it is ALWAYS the part that is missed. Add the following to your document BEFORE any other objects are declared. Make sure LPKNAME.LPK is the name of YOUR lpk: <OBJECT CLASSID=clsid:5220cb21-c88d-11cf-b347-00aa00a28331> <PARAM NAME='LPKPath' VALUE='LPKNAME.LPK'>
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A: PowerTCP uses what is known as ClassFactory2 licensing. This is a system developed by Microsoft as part of the COM architecture. All of the major development environments that we use support this type of licensing when a control is placed on a form, however, only VB or VBA type environments support it when the control is 'created' without a form. By created, this means Dimming as New, not CreateObject. Of the other environments, we currently only provide direct support only for dynamic usage in Visual C++. See the component wrappers for the code needed to instantiate an object with a license. ( Example: ITcp.h and ITcp.cpp included with the sample projects ) If you absolutely HAVE to use our products in a project without a form, you will need to get direction from the company that makes the environment ( Example: Borland, Sybase ) on how to use COM objects that require ClassFactory2 licensing. If contacting them is not an option or is too costly, we may be able to assist you if you have one of the higher level support options or purchase incident support.
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A: Absolutely! We ship samples written in Delphi, PowerBuilder and PowerBuilder (in addition to Visual Basic 6, Visual Basic 7 (.NET), C++, and ASP). In addition, we have customers using our products in FoxPro, Cold Fusion, Java Script, and other “COM-enabled” environments.
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A: Unlike other environments, the interface is automatically disabled when the cursor changes to an hourglass in Powerbuilder.

Including the code below will allow the hourglass to persist, but it will not automatically disable the interface. To produce the usual hourglass behavior, the interface must be explicitely disabled and enabled by the user.

//In the external global function declarations
FUNCTION ulong SetCapture(ulong a) LIBRARY "user32.dll"
FUNCTION boolean ReleaseCapture()
LIBRARY "user32.dll"

//In the script
ulong ll_handle, ll_rc
ll_handle = Handle(this)
ll_rc = SetCapture(ll_handle)
SetPointer(hourglass!)

//after done
ReleaseCapture()

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A: Yes. Your trial download is identical to the purchased product. The only difference is the trial download will only work for 30 days (in the case of ActiveX products) or will work for 7 days between each rebuild (for .NET products).
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A: .NET COM interop is used to utilize this control within .NET, and a Visual Basic 7 sample is provided.
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A: You can resolve a hostname to any IP address based upon loading metrics or security access privileges. When combined with the DNS control (from the Winsock Tool), you can even screen the hostname of each request before forwarding the request up to the next DNS server.
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A: You can intercept practically any request, and modify the response based upon your logic. For example, you could selectively restrict logins based upon username and time of day. You have complete control over the operation of the server.
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A: A proxy server accepts a connection and establishes another active connection to a final destination (that the application is a proxy for). To build a proxy using this product, use the TCP Server control to accept connections and use an associated TCP control to establish a connection to the destination server. As data is received, simply pass it back and forth between the two connections. Some proxies are much more sophisticated, and will monitor the connection and take action based on the protocol traffic it observes. This is sophisticated stuff, but is actually pretty easy to develop using PowerTCP.
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A: When using our controls in VBScript, you must specify optional parameters to prevent Type Mismatch errors.
For example, to zip a file with the FileStore, you need to create a SpanSettings instance:

Dim span
Set span = CreateObject("Dart.SpanSettings.1")
...
Zip1.FileStore.Zip("c:\Test\test.zip", span)
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A: The Server control, in fact, uses an internal Daemon control and dynamically creates TCP controls as each connection is accepted. The TCP controls are stored in a collection, and each time an event is raised a reference to the relevant TCP control is included as an event parameter. So if you want to spend the time doing this yourself, then there is no benefit. But if you want to “leave the coding to us”, then just use this product instead.
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A: The PowerTCP Mail Tool, available separately, can be used to easily forward mail to an intermediate server or final destination.
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A:

Yes, with reservations, particularly for server-side controls. Dart ActiveX controls require a message pump to process events. Unfortunately, .NET services do not implement a message pump. Therefore, server-side controls (Server, WebServer, FtpServer, etc) that require events to function cannot be used effectively in .NET services.

It may be possible for the user to implement a message pump on the application level in a .NET service.  We encourage our users to post working solutions on our forum.

Also, licensing of ActiveX controls in .NET requires the presence of the development license in the registry of the machine running the service.  The registry location of the license is:
HKEY_LOCAL_MACHINE / SOFTWARE / Dart / PowerTCP / License
This requirement is the same as for ASP deployment, and is further outlined on the Distribution page of the help file, under the heading "Distribution Under IIS."

As always, Dart controls can be used in a COM environment to develop Windows services (for example, with the PowerTCP Service control).

 

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A:

Yes, in most environments the ActiveX controls can be used in a scripting engine such as VBScript.

 

However, while the controls will work on 64 bit machines in compiled environments such as VB6 and VC++, they are limited to 32 bit Operating Systems in scripting environments.

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