Solving File/ Registry Permission Problems

These problems can be thoroughly frustrating to solve. Often poor coding techniques will lead to programs and installers trying to do things that a normal user will not have permissions to perform. To correct these you need to give the user the correct permissions in the right places without giving them too many rights. It has become common place for developers to assume that users will have full rights to the registry and filesystem on their PC ( a wrongful assumption).

Two programs that are very useful for solving such permission errors are by SysInternals (www.sysinternals.com) called RegMon and FileMon. They show you which processses are attempting to access which file/registry objects and what they are trying to do to them. It will also report any access errors in a meaningful manner.

A classic example of using these tools to fix bad programming techniques is troubleshooting the faulty registration of DLLs in installers. Often an installer will try and write to HKEY_CLASSES_ROOT when registering it’s DLL extensions. This is poor technique because normal user accounts do not have rights to write here. What should be done is that should be writing to the HKEY_CURRENT_USER\Software\Classes\ key instead. You can fix this problem by giving user rights to the whole HKEY_CLASSES_ROOT key or just to the keys that the installer is trying to access. However the best way to resolve these errors is to contact the DLL developer and get them to fix it.

By using this program you can configure some fairly granular permissions that stop the program errors occuring without granting full rights to the whole computer.