You just received that report that you get every week, you need to open it and complete that presentation for this morning, so you double-click the attachment and... the file can’t be opened. Outlook returns this error message: " Can't create file: file.zip. Right-click the folder you want to create the file in, and then click Properties on the shortcut menu to check your permissions for the folder." You know that you have the permissions on the folder, as the mail is in your Inbox, and you can also open other attachments just fine, so what’s with this error message?
Well, here’s what might have actually happened.
When you open an attachment in Outlook, a temporary copy of the attachment is created in a secure folder on your computer. This folder is called “Outlook Secure Temp Folder” and it’s a hidden folder, meaning that you will not find it if you just browse in Windows Explorer. However the folder can be opened if you know the path to it.
This folder keeps a copy of your attachment, but when you close Outlook, the temporary copies are removed as well. However, if you close Outlook while the attachment is opened, Outlook will not be able to delete the temporary copy from the secure temp folder, so the temporary copy will remain in the hidden folder.
Next time you open the same attachment, Outlook will create a new copy of that file and add a number at the end of the name of the file. For example, if the name of the attachment is PriceList.xlsx, Outlook will create a temporary copy named PriceList(01).xlsx . If Outlook cannot remove this copy of the file from the secure temp folder, the next time you open the attachment, another copy will be created and so on and so forth.
But here’s the catch. There is a limit as to the number of copies that can be created in this secure temp folder. Outlook can create only up to 99 copies of a file and when you try to create the 100th copy, Outlook will return the error message " Can't create file...”.
To get rid of this error message and be able to open the attachment, you can go to the registry editor (Start | Run, type regedit) and navigate to the following key:
HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\SecurityValue Name: OutlookSecureTempFolderData Type: REG_SZ
HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\SecurityValue Name: OutlookSecureTempFolderData Type: REG_SZ
The OutlookSecureTempFolder key contains the path to the Secure Temp Folder, so all you have to do is copy the path and paste it into a Windows Explorer window, then hit Enter.
Now you can simply empty the content of this folder. This will not delete your attachments, but only the temporary copies of the attachments stored in this folder and which could not be deleted (as they normally are) while exiting Outlook.
Next time you go to Outlook and try to open that attachment, you will see that the error message is gone.
If you delete the registry key that stores the path to the Secure Temp Folder, next time you open Outlook, a new registry key with a new value will be created, and this will be associated with a new secure temp folder that Outlook will start using.
However, this doesn’t mean that the old folder is deleted, but simply that it’s not used by Outlook anymore for storing the temporary copies. This folder will still exist on your computer, but it will be orphaned, which means that it will take up space on your system, but you will no longer be able to retrieve its location and delete it.