Hey Bertie
stlport64 version 5.2.dll seems to be referring to the Standard Template Library
which can be partly included with C++ redistributables.
I assume that the message you are receiving refers to a 64 bit download (stlport64),
the 5.2 would be the version number and the dll meaning that it is a library file.
Not sure how you would be able to fix that unless you check your Windows Updates and get an update
download prompt for a Visual C++ update. It's not a real good idea to go uninstalling and reinstalling the Visuall C++ package/s on your machine which you will find in Programs and Features so failing the update method I would be looking at maybe uninstalling the Acronis software, roll back the system with a restore point and then checking for Windows updates and reinstalling the Acronis software in that order.
In some circumstances the problem may relate to a virus/ malware in which case I would disable your current antivirus, download/ install and run MalwareBytes and see if it picks anything up.
You may also like to try running system file checker using the following command from an elevated command prompt:
Windows Orb (Start button)
All Programs
Accessories
Right Click Command Prompt
Run As Admin
Type the following: sfc/ scannow
(See this link for more details:
http://www.sevenforums.com/tutorials/1538-sfc-scannow-command-system-file-checker.html)
See if this picks up any system file errors and go from there
Hope this may be of some help
Cheers
