Is your modem running as fast as it could? Are the transfers between your PC and handheld device or digital camera too slow? You might not have the optimal COM port settings configured on your system. Here's how you can improve the performance of your serial devices.
Go to System Properties (Right-click on My Computer or go there via the Control Panel.)
Select the Hardware tab, and click on the Device Manager button to bring up the Device Manager screen.
Open up the Ports (COM & LPT) device branch to see the list of COM and LPT ports on your system.
Double-click on the COM port you want to optimize.
In the COM port properties window, click on the Port Settings tab.
Change the port's maximum transfer rate from the default 9600 bps to 115200 bps. This increases the serial bandwidth by 12 times!
Enable "Hardware Flow Control."
Click on the Advanced... button.
In the Advanced window, make sure that both the Receive and the Transmit buffers are set to their maximum values.
Finally, just close all screens by clicking OK on each screen.
Congratulations, your COM port is now configured at its optimal settings. Repeat these steps for your other COM port(s).