How Disable banner ads in Skype:
Before the many updates to Skype post-Microsoft acquisition, simply disabling the promotions options in settings was enough to rid your conversations of unnecessary spam. However, a new banner ad has made its way to the conversation window. This ad wouldn't be such a bother if it didn't often cut into the video feed area when going full screen. Thanks to Reddit user N19h7m4r3, you can disable ads through just a few steps. Here's how:
For Skype 6.x


For Skype 7.x
If you have updated Skype and the above options are not removing ads, you may need to perform a few extra steps to finally rid of the advertisements in your client. Here's how:Step 1: Make sure your Skype client is up-to-date by going to Help>Check for updates. Once finished, completely exit Skype.
Step 2: Head to C:\users\[your user name]\App Data\Roaming\Skype\[your Skype username]. You should see a config.xml file in this directory. Right-click it and choose Edit, then find the line that says <AdvertPlaceholder> and delete the entire line. Make sure to save your changes to the file before exiting. You can use Ctrl+F to find the line quickly.
Note: If you do not see the App Data folder, it's probably because you don't have Show hidden files enabled. Click the Organize button > Folder and search options > View tab > mark the radio button next to Show hidden files, folders, or drives.
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