Code signing is getting more and more important. It adds a digital signature to software files. These signatures can identify the publisher and verify that the software has not been altered or corrupted. The files themselves won't be altered, but a signature is appended to the executable. Malicious code can't be added to the file thanks to a checksum that would not be correct if there were a modification.

Since SP2 for Microsoft Windows XP was released, a security warning dialog indicates the "Unknown Publisher" if the digital signature is not included. Otherwise, the company name and an optional link is displayed.

Windows Vista comes with UAC - the User Account Control. These new security policies can make it so that only signed executables can be run on the system.

For software developers it is important to know that Microsoft requires all files with the following extensions to be signed with an Authenticode certificate to receive the Windows Vista Logo Certification:

• *.exe
• *.dll
• *.ocx
• *.sys
• *.cpl
• *.drv
• *.scr

Distributable files of software components like TX Text Control must be signed by the vendor of the component.

As a matter of course, we offer this service for our customers free of charge.

The process is quite simple:

1. Open a support case here and request your code signed files.
2. Our support engineers will ask you to send them your distributable files as a zip file.
3. After your files were signed, you will receive them by email.

We can offer this service only for version 14.0 of TX Text Control. If you have any questions about code signing or our sign process, feel free to contact me.