PRB: 32-bit TSP Fails to Install on Windows 95 with TAPI 2.1

ID: Q185336

The information in this article applies to:

• Microsoft Win32 Software Development Kit (SDK)

SYMPTOMS

When you try to add a 32-bit TSP (TAPI Service Provider) (such as ATSP32) using Control Panel applet on Windows 95 with TAPI 2.1 upgrade, the following message appears:

   The telephony system cannot perform that function at this time.
   Please try again later.

CAUSE

Typically, the use of Wide Character APIs within the TSP causes this problem. It is required that the TSP be written entirely in UNICODE. However, Windows 95 does not provide support for UNICODE. Therefore, the call to the Wide Character APIs causes the TSP installation to fail on Windows 95.

This restriction also applies to any Wide Character C-Runtime (CRT) string manipulation function calls, such as wcslen().

RESOLUTION

You can work around this problem by implementing a substitution function and replacing the offending function calls.

STATUS

This behavior is by design.

Additional query words: kbDSupport kbdss kbKernBase kbNoKeyword

Keywords          : kbTAPI 
Version           : WINNT:4.0;
Platform          : winnt
Issue type        : kbprb

Last Reviewed: August 4, 1998