Windows7ExceptionHack

Introduction

There were some reports about issues on Windows 7 where Power8 didn't run correctly. The hack-fix was implemented in version 1.4.1, but it requires manual activation. This page is about how to use it to fix the issue.

Symptoms

Power8 crashes right on start-up, or it crashes when you hover the main button with mouse. The exception message is quite big, and it starts with the following:

System.NullReferenceException: Object reference not set to an instance of an object. ---> System.ArithmeticException: Overflow or underflow in the arithmetic operation.

at System.Double.Equals(Object obj)

Examples can be found here: issue 9.

Cause

This is not an issue in Power8. The issue is caused by not identified 3rd-party component that interferes correct FPU-based calculation of Power8 UI elements sizes.

This issue has been seen for some time in the Internet, for example, here: http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/a31f9c7a-0e15-4a09-a544-bec07f0f152c

Solution

Power8 tries to utilize same fpureset() approach discussed at the page linked above. However since the solution is based on dynamic DLL load and method binding, this can be a performance hit, so hack is disabled by default.

To activate and use it:

1. Ensure any of these is installed in your system. If none - install last one: * C++ 2008 x86 * C++ 2008 x64 * C++ 2010 x86 * C++ 2010 x64 * C++ 2012
2. Open Power8.exe.config file in Power8 installation directory with notepad;
3. Find setting TryFpResetBeforeUiCtors and set it's Value to True (by default it's False);
4. Save file and start Power8.

NOTE: if Power8 will fail loading DLL from packages mentioned above, it will save a flag telling that this hack should be ultimately disabled. There will be no easy way then to clear this flag. So: DO NOT TRY TO USE HACK IF YOU DID NOT INSTALL C++ PACKAGES BEFORE.