TargetLynx QLD file becomes Read-Only when saved across the network - WKB7145

SYMPTOMS

• You can create the qld file normally.
• You save the file on a remote drive, i.e. not on the drive of the PC that you are logged in to.
• After making changes to the qld file, the file becomes Read-Only when you click the Save button, i.e. when saving the .qld file that is located on the different PC.
• The title bar displays [Filename] (Read Only)
• Sometimes you can click the Save button several times before the file becomes Read-Only.
• Closing and re-opening the qld file removes the Read-Only status, but the issue occurs again after further changes and saves.

In addition, sometimes the qld file may open Read-Only, in which case the warning 'File opened read-only as it is currently locked by unknown user' appears. This happens under the following circumstances:

• The user starts TargetLynx and opens a qld file that is located on a remote disk, e.g. on a shared folder on a different PC.
• While still in TargetLynx, the user chooses File > Open and opens a different qld file that is located on the network drive
• While still in TargetLynx, the user chooses File > Open and opens the first qld file again. It opens Read-Only, as already described.

ENVIRONMENT

• MassLynx 4.1
• TargetLynx
• QuanLynx
• Windows 7 only

CAUSE

This is a reproducible software bug, caused by a timing issue that occurs during lockfile processing in Windows 7.  As a result of the bug, the lockfile (see below) is not being generated or re-generated properly by TargetLynx.

FIX or WORKAROUND

The read-only status can be removed as follows:

1. Either close and re-open the qld file.

Or

2. In TargetLynx, click File >Refresh. When the Read-Only error appears (File opened read-only as it is currently locked by unknown user), click OK and then click File > Refresh again. The Refresh option clears the lock by re-creating the lockfile for the open qld file.

The issue is likely to keep occurring as long as the file is being saved across the network.

This fault was fixed in some releases of MassLynx 4.2 with TargetLynx XS (SCNs 977, 982, 984 and 976). However, unfortunately, the fix was not a good one, and introduced a new fault which means that in these releases, a .qld file now becomes read-only when saved to a folder (either local or remote) that does not have the Windows delete permission. This is a compliance problem for many customers with MassLynx security. See WKB20643.

Consequenly, in later releases of MassLynx 4.2 (SCN 986, 989 and 978), the 'fix' for the original locking issue was removed, so that .qld files could be saved to a folder which did not have the delete permission. However, in these releases, .qld are likely to become read-only when saved across the network to a remote folder.

May 2019: Development are currently trying to fix the network locking issue again.

The issue was finally fixed in SCN 997. 

Workaround

The issue with the locking of .qld files when saved across the network can be avoided by ensuring that the remote folder is open in Windows Explorer.

ADDITIONAL INFORMATION

Note: the lockfile is a filestream that is created when a qld fle is opened. It is deleted by Windows when the qld file is closed. The filestream has the same name as the qld file and is moved about with it, but it is hidden. TargetLynx uses filestreams as a mechnaism to protect qld files. 

This issue is not the same as the unreproducible Read-Only issue that sometimes occurs when a qld file is being opened, when the following error is displayed: 'File opened read-only as it is currently locked by [name of pc].