sidebar.exe is a program which is most likely legit. So, if sidebar.exe is on your system, it is most likely ok, and will NOT cause problems. Even if your PC is virus-free, it is still recommended to purchase a well-known antivirus with a good detection rate, in order to yourself yourself against threats.
Normally, this program is located in C:\Program Files\Windows Sidebar\sidebar.exe.
The MD5 checksum for this program is c5f3dacb10b9793334dc59b22a05b257.
This application does NOT run as a Windows service. This is usually a good sign.
This program uses the net to communicate. In this day and age this is quite normal. For example, most of the programs on your PC check for updates. In order to do this, Internet communications are necessary.
64-bit code has been detected. This program can use the full power of a modern computer processor.
The description extracted from the exe is Windows Desktop Gadgets.
File version 6.2.8400.0 (winmain_win8rc.120518-1423).
Company Microsoft Corporation.
Copyright notice © Microsoft Corporation. All rights reserved..
sidebar.exe appears to have visible windows. This is good because it doesn't work in a kind of stealth mode. Its operation is clearly shown to you.
A digital certificate is missing from this program. The authors did not bother to sign it. This is probably bad.
This application does NOT have an uninstall routine stored in registry.