There is a chance that if you have antivirus/antispyware/firewall software installed that it is interfering with the download and throwing up this error. Try adding Impulse.exe as an exclusion in these types of apps if you have them. If you are unable to do this or if it does not help, you may need to temporarily disable them and then try again.
If you still cannot get anywhere, please send us your Impulse error log and your startup/dxdiag info as detailed here: https://forums.stardock.com/341573
