This is to do with the file permissions problem on vista.
You will have to change the permissions on your files (or hard drive, but this often does not filter through to all directories).
Right click on your hard drive - select properties - security, then edit the permissions.
(You may have to repeat the above for various directories).
I'm having the same exact issue, Vista 64.
I use Dreamweaver CS3 daily and till this morning everything was fine.
Suddenly began getting the symptoms described above, access denied, then file disappears.
Already tried 25 different ways of taking ownership and full permissions on a single file, entire folders and the entire D:\ drive where I normally work. Enabled the Vista Administrator account (hidden and disabled by default on Vista), and tried every ownership, permission possibility I could think of from that account also.
Nothing fixes it so far.
It's definitely a permissions issue though.
I confirmed that the issue DOESN'T exist when I sign in as Administrator and use Dreamweaver.
Signed in as myself (with Administrator rights), the problem exists.
I too have this issue and regardless of what permissions I set on the file, folder whatever, I get the problem sporadically, there is no rhyme or reason to why it happens.
I posted about this a while ago here:
This issue is now resolved for me.
I can create the issue and cure the issue at will.
The problem was Vista Explorer's preview option.
When I turn it on the issue occurs.
Turn option on: Organize / Layout / Preview Pane
Open Dreamweaver and a sacraficial file, edit and try to save it...BINGO...access denied, file disappears etc.
Turn off the Preview Pane and issue is cured.
Tested your suggestion and tried about 5 different times, but I didn't get one locked file while the view pane was 'on'.
Hmm... I'll experiement with this over time and see if it is the issue... as I said originally, there is no rhyme or reason for this stooopidness :-)
Thanks for the tip - hopefully it may help other people, but for me, I'm on the fence until I test further.
Upgrading to Windows 7 64-bit, I found that Dreamweaver cannot update files created in earlier sessions because of the Windows 7 User Access Control.I found this when I tried an approach of saving my edits into a new file, deleting the old file, and saving the new file under the old file's name.
Selecting Edit/Delete on right-clicking a file in Dreamweaver's Files window a got a dialog box saying File Access Denied: You'll need to provide administrator permission to delete this file (I am an administrator on this workstation). Clicking on Continue, the screen dims and the User Access Control window pops up, asking "Do you want the following program (Dreamweaver) to make changes to this computer?" After clicking on Yes, the file is deleted but the permission must be granted separately for each subsequent file.
This is a slow workaround, but it works. Nothing in the Windows Explorer window or file permissions in Windows made a difference.
I'm not sure if this is one of those "Windows Undocumented Features" or a poor programming handshake between Adobe and the operating system, but I commend this to someone's attention to find and fix the cause, or to share a more direct workaround.
The problem for me in Vista was that "User Account Control" was turned ON. I had a "permission denied" problem in Eclipse when I tried to create a new project. I went into The Security Center Control Panel and turned OFF "User Account Control", Restarted the computer, and all my permissions problems went away.
Windows is so dumb sometimes.
I can confirm the solution is to do with preview pane in Vista 32 bit. the problem affects notepad and dreamweaver but not other editiors. For example wordpad works fine. It is also only confined to files of type .htm ot .html. .php are not effected .
preview pane introduces a security hole which allows external uses to see details of your computer. Microsoft have obviously attempted to plug this but in my opinion very badly.