Broken context menu

[z]

When I right click on .bat files, the top-most "Edit" option is missing. How do I fix this? I notice that under Folder Options, there is no entry for the BAT extension. However, in the Registry under HKCR, .bat is present and contains a subkey PersistentHandler that seems to point to the right thing. The freeware program ContextEdit also seems to think that everything is in order, although it's obviously not. Other file types work fine. I'm running Win2k SP2.