When a user opens an attachment from within Outlook, the file is saved to a hidden location on the workstation they are using. Sometimes, an end-user would edit this copy of the document, save it, and then when they go to re-open it they can’t find it.
The hidden folder location is stored in the Registry under the “OutlookSecureTempFolder” key. The folder name is randomly generated. Search results do not bring up the location. Below is a quick-list of the registry entry you want to look at to give you the full folder name:
Click Start, click Run, type regedit in the Open box, and then click OK. (Run from an elevated command prompt.)
Locate and then select the following registry subkey:
On the Edit menu, point to New, and then click DWORD (32-bit) Value.Type NewItemsUseDefaultSendingAccount, and then press ENTER.In the details pane, right-click NewItemsUseDefaultSendingAccount, and then click Modify.In the Value data box, type 1, and then click OK.Exit Registry Editor.