Problem:
Local clients using OPC Classic fail to connect to the server and may report an error like 0x8007041D. This error code means that the service did not respond to the start or control request within time.

Solution:
COM requires the use of libraries that are part of Microsoft's Object Linking and Embedding (OLE) technology. If these libraries have been unregistered by another application, local clients will cease to connect. For information on registering the libraries, refer to the instructions below.

1. Launch the Command Prompt, and select Run as Administrator.
2. Change the directory to C:\WINDOWS\System32 or C:\WINDOWS\SysWOW64 on a 64-bit operating system.
3. Enter the following commands one line at a time:
   regsvr32 ole32.dll
   regsvr32 oleaut32.dll
   regsvr32 opcproxy.dll
   regsvr32 opccomn_ps.dll
   
   Note: Not all commands will report success.
4. Reboot the computer.