Two ways: Reset the Hand Tool by ctrl-clicking or right clicking on the icon in the Options bar.
Reset Preferences: Hold down cmd-option-shift, the starting Photoshop. You will see a "delete settings?" dialog. Click "Yes" and let Photoshop finish loading.
See if one of these fixes the Hand Tool.
Thanx. Will try next time I encounter the problem. And get back to you.
I'm thinking you could do this and possibly fix the Hand Tool before the problem arises while you are working on something important.
Also, do you know when this started? Upgrading to Yosemite has been known to damage CS5 installs.
Yes. It appears to have started happening since I bought a new Mac (ie, so upgraded to Yosemite).
That said,I am somewhat reluctant to reset all my preferences, as you suggest... I have so many personalised brushes, etc... I would hate to lose all that...
How would deleteing preferences affect all my preselects..?
You will keep your custom brushes and other Presets. They will not be removed.
Workspace may be affected so save that. If you use large thumbnails in your layers, you will have to set that after the reset.
I guess you installed CS5 from your disks on your new Mac. Migrating or restoring from backup is never a good idea.
If the reset does not work, you may have to reinstall.
Also if you want to wait until you have this problem, go ahead and and take time to back up your Presets to be safe.
Resetting the Hand Tool won't touch anything, so it is Plan A.
DId you install the WhiteWindowWorkaround plugin to avoid some of the known MacOS bugs?