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Using IE6 With Visual Studio 2008

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Here's a little scenario I came across the other day. I've forwarded the information to development, so it's pending further investigation. I still thought it would be a good idea to publish the scenario though.

Visual Studio 2008 + FTP = Possible trouble

It seems like there might be a bug in Visual Studio 2008 when it comes to projects that you access via FTP. I don't know how common it is to use FTP to access & deploy your projects. It would be really interesting to see some genuine statistics, but since FTP is highly insecure I guess it is very rarely used. This, I guess, is probably the reason why this little glitch slipped through in the first place.

File change notification works fine...

Consider the following scenario:

  • You're working on a web project using FTP
  • You've downloaded a file to your local cache and you're doing some changes.
  • Another client changes the file
  • You attempt to save the file, but the original file on the server has changed so it no longer matches the one in your local cache.

This causes a warning to pop up with the following information:

A more recent version of the file [File Name] has been saved to the web on '[Date]' . Do you want to replace the server file with your local file?

...overwriting the file doesn't

Clicking Yes you'd now expect Visual Studio to simply overwrite the file on the server. Unfortunately this is where the glitch rears it's ugly head. Instead of overwriting the file it gives you the following error message:

Cannot save the file [File Name] to the Webserver. The file [File Name] has been modified by (unknown) on [Date] [Time Zone].

Continuous attempts at saving will have no effect. The error pattern will repeat, displaying the two dialogue boxes over and over again.

Alternative solution

My customer originally fixed this by selecting everything in the editor, copying it to Notepad, canceling the operation in Visual Studio, reopening the connection, pasting the contents from Notepad into the document and saving. Fortunately there's an easier way to resolve it.

Simply click the Refresh-button in the Project Explorer window. Visual Studio will then ask you if you wish to update your cached version of the files you've edited. This may sound like you're going to perform a revert-to-save operation on the pages you've edited, undoing all the changes, but it's actually not the case. Visual Studio will simply refresh the files in the cache, not the ones in the editor. When Visual Studio has finished refreshing the cache it will notice the inconsistency between the files asking you if you want to update the file in the editor as well. At this point you should answer "No", unless you want all your changes undone.

My thoughts about this

Obviously this shouldn't happen. You shouldn't have to refresh the cache in order to overwrite the files. Still, as I mentioned before I believe there are two reasons why this problem managed to slip through the cracks.

  • FTP is unsafe. Even the password is sent as clear text and can be intercepted by anyone. For this reason I would assume that FTP is quite rarely used.
  • In order for the problem to occur you need to trigger a file change notification on the file in question. For normal scenarios this would mean that another client accesses the FTP-site at the same time and changes the file as you're working on it. This type of on-the fly editing without any form of source-control would be highly risky in a production environment and you'd most likely use some other means of connection while in development.

Visual Studio 2008 + FTP + Internet Explorer 6 = More trouble

Unfortunately the problem doesn't end there.

It turns out that if you are using Visual Studio 2008, are working on a web project using FTP and have IE6 on your machine, then IE will act as if a file change notification has occurred after 90 seconds wether this is true or not. This means that after 90 seconds all your attempts to save will trigger the behavior described above. The refresh cache-approach still works, but it will quickly become quite tedious.

According to the prerequisites for Visual Studio 2008, Internet Explorer 6 is a minimum requirement, so there is nothing documented on IE7 being a necessity in order to run Visual Studio 2008.

Alternative solution

So far I only know of one way to resolve this. Install IE7. You'll still encounter the first potential problem if you have more than one client working simultaneously on the same application, but as I've already mentioned, this sounds like a very unlikely scenario.

/ Johan

Comments

  • Anonymous
    May 05, 2008
    The comment has been removed

  • Anonymous
    August 13, 2008
    IE7's no better. I've been trying to fix this for ages. I work as part of a distributed team and the only way for us to work is via FTP. We all would live to work in VS08 but the FTP just will not work :-(. So we use dreamweaver for our sins. It would be nice if Microsoft would fix this! or drop it as a bad idea then I can stop trying to get it to work.

  • Anonymous
    September 08, 2009
    Hi I get the message :- A more recent version of the file [file] has been saved to the Web server by [user] on [datetime]. Do you want to replace the server file with your local file? I think this is because other users edit files on the website using other editors.  I'm using Visual Studio 2008.   Using the "Refresh" option doesn't resolve the problem.  I can't find where this information is being cached on my machine and can't find many references to this anywhere. The option I'd like is to either clear my local cache (wherever that might be) or just refresh it from the website every time I open the project as I don't work locally. Any help or suggestions greatly appreciated.

  • Anonymous
    September 08, 2009
    Hi Found the answer:  just need to clear the cache manually. Thanks

  • Anonymous
    October 06, 2009
    Thank you for the find, Ian.

  • Anonymous
    February 05, 2010
    Hey, just wanted to point out this bug (or something very similar) is still in VS2010 beta 2 (using ftp).  It seems that I have to save at least once every two minutes. If I go 5 minutes without saving, it will prompt me with "Do you want to replace the server file with your local file?" and then fail when I click "yes". I have been copying the whole contents of the file, and closing down the file, waiting a few seconds, and reoping it (which will prompt me to see if I want to overwrite my cached copy), after clicking yes, I paste and resave. Unbelievably annoying.   Re: Still using FTP We use FTP here all the time for development. Yes the password is in clear text but since the ftp access IP limited it really doesn't matter to us. It's easier to setup for remote access and people are familiar with it.