Actually it is not ViaBTC impeding me to withdraw, but Electrum. When I enter the amount, it tells me that it is too small.
Simple question - where are your bitcoins at this very moment? Still in your ViaBTC account, or did you already transfer them over to your Electrum wallet? Im guessing you are trying to withdraw your coins from ViaBTC into Electrum, right? If so, just know that Electrum has nothing to do with setting restrictions on withdrawals from ViaBTC. The only way Electrum can get in your way is if you try sending an amount from Electrum thats less than the recommended transaction fee, which is not the case here. But other than that your Electrum wallet wont interfere with a ViaBTC withdrawal at all.