Disable OneDrive in Office 365

Disabling SkyDrive by using the Registry Editor

Launch the Registry Editor by opening the Run dialog box and entering regedit.
When the Registry Editor opens, navigate to the following key: HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common\SignIn.

If the SignIn key doesn’t exist, create it by right-clicking on Common New Key SignIn.

In the right pane of the SignIn key, create a new DWORD value named SignInOptions.

Double-click on SignInOptions and change its value to 3. To restore SkyDrive functionality, simply set the SignInOptions value to 0.

Browser Hijack

Use ADWCleaner

Delete all IE/Chrome data files C:\users\username\appdata & also check roaming/local & local low folders.

Also check the DNS settings to make sure they have not been modified.