If you recently cloned repository to the Windows PC, made some change and try to perform commit via TortoiseHG, you may get the following error:
Trouble committing file.
Access is denied
In order to solve it go to the Windows explorer and open properties of the repository folder. Then on Security tab click Edit and ensure that Users group has Full control rights:
After changes will be applied to all files and subfolders in the folder, error should disappear and commit should be successful.