[MCL-5546] Unable to save download (caused by incompatible software)

Mod Notice

This issue seems to be caused by incompatible software, removing it fixes the issue.

If you have this issue, please check whether you have installed any incompatible software installed on your computer. If there is, uninstall it. If there isn't, please contact 💬 Community Support. Please don't post comments here, this is not a support forum.

For Windows:

Open the Start menu (Windows button)
Type 'Control Panel' and open the first result
Click on 'Uninstall a program' right under Programs
Right-click the incompatible program and choose 'Uninstall', then follow the on-screen instructions.

After the uninstall, restart your PC for the changes to apply.

Example of issue: http://paste.ubuntu.com/23950125/
xml seems to be client-1.7.xml

HJT reports: http://paste.ubuntu.com/23950156/ http://paste.ubuntu.com/23950162/
Seems like each player is getting a different message, got 8 people right now with the same one in IRC.

Restarting the launcher sometimes gives a different file.