There are two possible reasons:

1. Your navigator doesn't accept Javascript:

When using Internet Explorer, you can go to the menu "Tools" --> "Internet Options" --> tab "Security" --> Security Level for this Zone.
In the opened window, select enable under "Active Scripting".

2. Your navigator doesn't accept cookies:

When using Internet Explorer, you can go to the menu "Tools" --> " and select the " --> tab "Confidentiality" and place the level on "Medium".

If the problem continues, we advise you to try another Internet navigator.
You can download and install:
Firefox