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Azure web app timezone error in asp.net webapi

I have web app in azure paas environment. I need to convert the time in different timezone, i have following code which run perfectly fine on dev machine but when i deploy on azure paas environment it throw error
TimeZoneInfo serverTimeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById(TimeZone.CurrentTimeZone.StandardName);
return TimeZoneInfo.ConvertTimeToUtc(_lastUpdatedDate.Value, serverTimeZoneInfo);
First line throw exception. Error getting value from 'DateCreated' on 'ViewModels.Orders.OrderActivityViewModel'

A few things:
Don't use the TimeZone class. It is obsolete. Use only the TimeZoneInfo class.
The StandardName is NOT the same as the Id for all cases. It is also impacted by OS language, where the Id is not.
The local time zone's Id is at TimeZoneInfo.Local.Id, though there's no point in finding it by Id when you already have it. You'd just use TimeZoneInfo.Local.
If you're just converting local time to UTC, you don't need to mess with time zones at all, just use .ToUniversalTime() on your original DateTime or DateTimeOffset value.
The server's time zone probably already is UTC. That is the default in Azure anyway. Thus it isn't going to do anything at all.
If necessary, you can change Azure App Service's WEBSITE_TIME_ZONE setting (on Windows only), but I don't recommend that. If you have a specific time zone in mind, then you would pass that ID into TimeZoneInfo.FindSystemTimeZoneById.
As others pointed out, the error you reported isn't in the code you gave, so likely none of this is going to help you.

How to save clicking counter in c#

I build web-site and want to count clicks on some button. I create and try this class of counter:
public static class Counter
{
public static int counter = 0;
}
Every time I click on the button the counter is increament (counter++) ans I see it in my site, But, if I close the chrome and enter again to my site the counter starts from zero.
How can I save the counter? "Static" dont need to do that?

My bet is that it happens because the application space is flushed - it shouldn't reset just because you closed your browser window, thus abandoning the current session (if the session cookie isn't persistent, that is.)
Visual Studio may republish your files (if using a remote IIS) or just plainly restart a local IIS Express instance, depending on how you set your development environment; I do believe setting a specific content as Static would cause it to be available to all current sessions.
That said, you may want to keep it under the current session (using the Session object).
Optionally, if you want to persist information in between server restarts, you may try reading and writing to a local storage, such as a plaintext or XML file. You can find a very nice article about this on the following link:
http://www.codeproject.com/Articles/544839/Implement-ASP-NET-custom-XML-file-configuration
A more sophisticated version would use a local (or remote) database, for example.
Hope it works for you.

static fields are unique per-process. Depending on your application pool configuration, you could have 2, 20 or 100 copies of that.
They're also not thread safe. There are very, very few instances (pun) where a static member is appropriate.
Just off the top of my head, a particular "instance" of a static will disappear when:
The application pool is recycled. On IIS, this defaults to 20 minutes of inactivity.
The application process exits (you may have multiple processes running within your app pool). This happens as part of (1), but will also happen if, say, you're using the Visual Studio debug web server (Cassini), have your project configured to launch the site for debugging, and close the browser that was launched initially. (This happens because VS considers closing the browser that it launched equivalent to saying "I'm done playing. Back to coding now," or hitting the stop button.)
Another thread overwrites the value you've stored (google "race condition.")
You really, really should be storing this in a database. If you're building a website, you need a database anyway. ANYTHING related to application state should be stored in the database.
ALSO, this really, really shouldn't be happening server-side. Are you really performing a postback every time someone clicks anywhere on a page? If so, you have JavaScript in place to handle that, so just skip this insanity, have said script fire off an AJAX request, and have the target handler log it in the database.

Looks like your using a web site so presuming ASP.net. There are a number of ways to store the information. Database could be one or a persistent cookie could be the way to do it. See this article on how to create cookies: How do I set/unset cookie with jQuery?

You can try save it in session and then it will stay until the session is time out(20 minutes) if you want it to long time just write it to file in known location and when you close the web write the value to the file and when the web is up again take the vakue from the file.

How is local determined in ToLocalTime()

When using ToLocalTime(), how is local time determined? Is local time from the server or the client? My assumption would be the server running the application.

It is the local time zone of the computer that code is running on. In an ASP.Net application, the code runs on the server - so that's the time zone that it will return.
The behavior of this function is actually dependent on the .Kind property of the source value. From the MSDN link you gave:
Utc - This instance of DateTime is converted to local time.
Local - No conversion is performed.
Unspecified -This instance of DateTime is assumed to be a UTC time, and the conversion is performed as if Kind were Utc.
This is non-obvious behavior. You can read other related problems with the .net DateTime class here and here.
A few other points:
If you follow best practices, you will set the server's time zone to UTC.
If you are trying to display time in the user's timezone, you'll have to use one of these strategies.

ToLocalTime(), in this case, executes on the server. Therefore the time is evaluated on the server, and it'll return the server time to the client.

It is the local time on the server.

Local here is the timezone of the machine that the function executes on.

Getting files info (accessed/modified dates) from FTP server (C#)

I'm creating a program which downloads files off various types of servers, such as network paths or HTTP servers, based upon criteria. So far I have it working based upon a regex, but I'd also like it to find files newer (last accessed, modified or created) than a given date. This is easy in the network path type because I can access the FileInfo for that file, but all I have in my FTP server is a 'line' string which obviously just holds the file name.
Is it easy/possible to access the last modified/accesesed/created dates for a file on an FTP server in C#?

Unfortunately FTP provides only limited information about the remote file. With default LIST command you get OS-specific response where one date is usually present (this is usually last modification time). With MLST/MLSD extension commands you get machine-parsable response string but also with just one time.
The exact way to get the date depends on what component or class you use to access the FTP server.
If you need to get more than one date (eg. date of creation and last access), and you can go SFTP route, I'd recommend using SFTP instead.

You could use a third party library such as edtFTP to connect to the FTP server and inspect the last modified/created (not sure if you can get the the last accessed timestamp) timestamps. Its quite an easy library to use:

Proxying Videos locally with a TCP Socket

I've been really interested in adding support for video podcasts to Media Browser.
I would like users to be able to navigate through the available video podcasts and stream them from the internets. That's really easy cause media player etc.. will happily play a file that lives in the cloud.
The problem is that I want cache these files locally so subsequent viewings of the same episode will not involve streaming and instead will play the local file.
So... I was thinking, why not host an HttpListener and as media player asks it for bits of the file, have the HttpListener download and store it locally. Next time a user plays the file we will already have portions of the file locally.
Does anyone know of example code that uses HttpListener for proxying?
EDIT
The idea would be only to proxy simple streamable content like MP3 or Mov.
The bounty will go to an actual implementation.
Here is the API I would like:
// will proxy a uri on the local port, if cacheFile exists it will resume the
// download from cacheFile.
// while the file is downloading it will be name cacheFile.partial, after the
// download is complete the file will be renamed to cacheFile.
// Example usage: ProxyFile("http://media.railscasts.com/videos/176_searchlogic.mov", 8000, #"c:\downloads\railscasts\176_searchlogic.mov")
//
// Directly after this call http://localhost:8000 will be the proxy stream, it will be playable locally.
void ProxyUri(Uri uri, int port, string cacheFile)
Edit 2
HttpListener is looking pretty unpromising I will probably need to do the work at a TCP socket level as HttpListeners seem to require the program runs as admin which is going to be really tricky.

I hadn't done anything with HttpListener before, so I thought this would be a nice little exercise to bring myself up to speed with it - and so it proved. I implemented it as a single ProxyListener class whose constructor takes the parameters of the ProxyUri function you specified. Once you obtain an instance, you start it listening (and potentially downloading) by calling its Start method. When you're done with it, call Cleanup.
There are one or two rough edges but basically it works as per your question. To test it, I built it up as a console application with a Program class which accepts input lines consisting of (uri, port, filename), space-separated, creates the ProxyListener instances and starts them. You can run this console application, type in a suitable line, and the downloader will start (printing out progress to console). Simultaneously you can e.g. fire up IE and fetch the file from the specified port, and you will be able to download it while the downloader is still working. The "uploader" progress will be printed to console, too.
I'm having a bit of trouble pasting it in here, maybe due to size (it's not that big, but bigger than the snippets you normally see here - the ProxyListener class is a tad under 200 lines). Does it sound interesting? If so, I'll post it to a pastebin and update this answer with a link.
Update: Posted as a gist.
Note that you will need Administrator privileges to run the program, since HttpListener requires this.
Update 2: Under certain circumstances, it is not necessary to have admin privileges to run HttpListener. See this link and this one. The idea is, if you can reserve an URL namespace during installation time, then the user does not have to have admin privileges if listening against that namespace.

Streaming was not designed to be saved, and also these protocols are very custom and very complex to implement, streaming sessions do lots of validation and synchronization which will be extremely difficult to imitate. Of course it is not an impossible task, but its fairly big task to do. Only other way is to read and save it as local media file, and use that as a reference. Because you can use windows media encoder to read stream and write stream data as local file, but it still may not allow you to do copy protected data.

Did you consider using HTTP proxy with caching features?
Like:
Apache httpd with mod_proxy and mod_cache
Squid
See also Web Cache # wikipedia
If you want your application to have such web cache component, I suggest you look for Web Cache implementation in .Net, and not code it from scratch.