Did you just find a file that has been digitally signed by TAC-Soft Limited? If so, please read on.
You'll typically see TAC-Soft Limited when running the file. The publisher name is then displayed as the "Verified publisher" in the UAC dialog as the screenshot shows:

You can view the additional details from the TAC-Soft Limited digital signature with the following procedure:
Here is a screenshot of a file that has been signed by TAC-Soft Limited:

As you can see in the screenshot above, Windows reports that "This digital signature is OK". This implies that the file has been published by TAC-Soft Limited and that no one has tampered with the file.
If you click the View Certificate button shown in the screenshot above, you can see all the details of the certificate, such as when it was issued, who issued the certificate, how long it is valid, etc. You can also view the address for TAC-Soft Limited, such as the street name, city and country.
COMODO RSA Code Signing CA has issued the TAC-Soft Limited certificates. You can also see the details of the issuer by clicking the View Certificate button shown in the screenshot above.
The following are the TAC-Soft Limited files I've collected, thanks to the FreeFixer users.Unfortunately I don't have any scan result from VirusTotal available for the TAC-Soft Limited files at the moment. The scan results will appear here as soon as a FreeFixer user uploads a file digitally signed by TAC-Soft Limited.
| Detection Ratio | File Name |
|---|---|
| Not available | mcqmsetup.exe |
The analysis is based on certificates with the following serial numbers: