Update via TMS Subscription Manager failed

I want to do Updates with the Subscription Mananger. If i push the button Update i get the message: 

Filesize incorrect. Restart Subscription Manager and retry. 

Can anyone help me? 

Can you try to
disable software that can interfere with an internet connection like a
Firewall, proxy, antivirus.

which port is used?

The installer makes a HTTP connection via port 80 to http://www.tmssoftware.com/

port 80 to http://www.tmssoftware.com/    is open

no proxy and antivirus disabled
but it doesn't work

Can you try to directly download the product from the “My products” page after login on our website?

yes ... it works

If a file got corrupt in the cache, you could also try to delete files under


i deleted all but it doesn't work

If you are sure that no antivirus, proxy, firewall, websecurity software is interfering, try to use a (free) HTTP analyzer tool like Fiddler to analyze why the installer can't download the file.

I have same problem on Win XP, But Windows 10 no this problem!

Can you check with a free tool like Fiddler https://www.telerik.com/fiddler what is happening to the HTTP requests performed from TMS Subscription Manager?