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Issue with datetime parsing

When I tried to parse the "2017-09-25T11:06:55+00:00" date string using TryParse method, I get the following output:
{9/25/2017 7:06:55 AM}
So, it's looks like 11 a.m. is getting converted into 7 a.m. Not sure why is this happening this? Is it because of +00:00??
What do I need to do so that parsed Datetime output is same: i.e. {9/25/2017 11:06:55 AM} ?
I tried using Current locale/culture and DateTime Styles. Assume Local but no luck.
(Note: I'm in the eastern time-zone)
Thanks.

You are using the UTC timezone (+00:00), but apparently, you or your PC is in -04:00 timezone.

If you can use DateTimeOffset, then I tend to prefer it. You get time zone info preserved, and you have access to both local and UTC datetime properties off this object.
var dt = DateTimeOffset.Parse("2017-09-25T11:06:55+00:00");
Console.WriteLine(dt.DateTime); // 9-25 at 11:06
Console.WriteLine(dt.UtcDateTime); // 9-25 at 11:06
Console.WriteLine(dt.LocalDateTime); // 9-25 at 07:06
If you know you're always going to be dealing with UTC, you can just parse by adjusting to universal like so:
var dt = DateTime.Parse("2017-09-25T11:06:55+00:00", CultureInfo.CurrentCulture, DateTimeStyles.AdjustToUniversal);
Console.WriteLine(dt); // 9-25 at 11:06

When you parse it initially it's the correct value, it's just now adjusted to be in your timezone. You can force it with ToUniversalTime :
DateTime.Parse("2017-09-25T11:06:55+00:00").ToUniversalTime().ToString("yyyy/MM/dd HH:mm:ss tt")
output
"2017/09/25 11:06:55 AM"

You want to parse correctly UTC DateTime and to have 9/25/2017 11:06:55 AM instead of 9/25/2017 7:06:55 AM. +00:00 is not correct UTC format, you need to change it to "2017-09-25T11:06:55z".
Here is working example

Date conversion

I need help to convert current date to "Tue Nov 4 00:00:00 UTC+0530 2014" date format
using C#.
Say I have date like : DateTime dt = DateTime.Now;
Now, how can I convert it in mentioned format.

DateTime.ToString(string) allows you to specify a format for your date. You can construct a custom format using Custom Date and Time Format Strings.

I feel like taking risk to answer your question but anyway..
A DateTime doesn't have any implicit format. It just have date and time values etc.. That's why it is not possible to have any format. But string representations of them can have a format. Formatting a DateTime is easy, just need to use DateTime.ToString() method with a specific culture. (In your case looks like InvariantCulture is a good candidate)
DateTime dt = DateTime.Now;
dt.ToString("ddd MMM d HH:mm:ss 'UTC+0530' yyyy", CultureInfo.InvariantCulture);
returns
Tue Nov 4 14:20:36 UTC+0530 2014
AFAIK, time zone abbreviations are not standardized and that's why there is way to parse them besides literal string delimiter. Also since a DateTime doesn't keep offset value, you need also parse it as a literal string delimiter
If you would want to +05:30 instead +0530 as a result, "zzz" custom format specifier would be a nice choice since it gets + or - sign, hours and minutes part offset of local operating system's time zone from UTC.

Based upon your suggestions, I build this code
DateTimeOffset localTime = DateTimeOffset.Now;
string.Format("{0:ddd MMM d HH:mm:ss} UTC+{1} {0:yyyy}", localTime, localTime.Offset.ToString("hhmm"));
and its generating correct format:
"Tue Nov 4 18:25:48 UTC+0530 2014"

Parse Date Time from US Time zone to Datetime.

How to parse below date time string?
2014-01-17T09:59:24.000Z
I tried below code but its, not working.
DateTime.ParseExact("2014-01-17T09:59:24.000Z", "ddd MMM dd HH:mm:ss %zzzz yyyy", CultureInfo.InvariantCulture);

With a string like "2014-01-17T09:59:24.000Z"
You can just use DateTime.Parse("2014-01-17T09:59:24.000Z")
From The Documentation:
The string to be parsed can take any of the following forms:
A string that includes time zone information and conforms to ISO 8601. In the following examples, the first string designates Coordinated Universal Time (UTC), and the second string designates the time in a time zone that's seven hours earlier than UTC:
2008-11-01T19:35:00.0000000Z
2008-11-01T19:35:00.0000000-07:00

From DateTime.ParseExact
Converts the specified string representation of a date and time to its
DateTime equivalent using the specified format and culture-specific
format information. The format of the string representation must match
the specified format exactly.
Clearly your string representation and format is not the same.
You can use it like;
var date = DateTime.ParseExact("2014-01-17T09:59:24.000Z",
"yyyy-MM-dd'T'HH:mm:ss.fff'Z'",
CultureInfo.InvariantCulture);
Console.WriteLine(date);
Output will be;
1/17/2014 9:59:24 AM
Here a demonstration.
For more information, take a look at;
Custom Date and Time Format Strings

The value you have, 2014-01-17T09:59:24.000Z is an ISO8601/RFC3339 formatted timestamp. The Z at the end is significant, which means that it represents UTC.
You have two options to correctly parse it:
You could parse it to a DateTime that has DateTimeKind.Utc for it's .Kind property:
DateTime dt = DateTime.ParseExact("2014-01-17T09:59:24.000Z",
"yyyy-MM-dd'T'HH:mm:ss.fffK",
CultureInfo.InvariantCulture,
DateTimeStyles.RoundtripKind);
Or, you could parse it to a DateTimeOffset, where UTC will correspond to an offset of zero:
DateTimeOffset dt = DateTimeOffset.ParseExact("2014-01-17T09:59:24.000Z",
"yyyy-MM-dd'T'HH:mm:ss.fffK",
CultureInfo.InvariantCulture);
Some of the other answers here are close, but are forgetting to actually consider the Z in your string, using the K specifier and the DateTimeStyles.RoundtripKind parameter. These are important, for without them you will likely end up with a resulting DateTime that has DateTimeKind.Unspecified, which could get treated as local time in certain time zone conversion functions. If you use either of the options I gave you, then the meaning of the Z is preserved.

Converting the string "20111027" to a DateTime with a timezone of GMT

I have a string in this format: "20111027", i.e. of the general format: "yyyyMMdd".
How do I convert this to a DateTime having the timezone GMT?
This code does some conversion, but it's unclear what timezone would be used:
DateTime date = DateTime.ParseExact(dateString, "yyyyMMdd",
CultureInfo.InvariantCulture);

Use a DateTimeStyles of AssumeUniversal:
DateTime date = DateTime.ParseExact(dateString, "yyyyMMdd",
CultureInfo.InvariantCulture,
DateTimeStyles.AssumeUniversal);
From the docs of DateTimeStyles.AssumeUniversal:
If no time zone is specified in the parsed string, the string is assumed to denote a UTC.
Sounds like exactly what you want :)
(Alternatively you could use Noda Time and parse it to a LocalDate. It only represents a date, after all, so why use a type which cares about times and time zones? :)

From the documentation:
If s does not represent a time in a particular time zone and the parse operation succeeds, the Kind property of the returned DateTime value is DateTimeKind.Unspecified.
You can change the Kind using DateTime.SpecifyKind:
date = DateTime.SpecifyKind(date, DateTimeKind.Utc);

When using DateTime.ParseExact, how do you specify what the timezone is of the given date?

Given the following:
DateTime.ParseExact(timeStamp, "yyyyMMdd-HH:mm:ss.fff", System.Globalization.CultureInfo.InvariantCulture);
How do you specify that the given time is UTC? Right now the result is giving it my current timezone.

Add DateTimeStyles.AssumeUniversal, since it's not specified in the format.
DateTime.ParseExact(timeStamp, "yyyyMMdd-HH:mm:ss.fff", System.Globalization.CultureInfo.InvariantCulture, DateTimeStyles.AssumeUniversal);

You can include the timezone offset at the end of the parse string like so
DateTime.Parse("2011-01-01 12:00:00-5:00")
http://msdn.microsoft.com/en-us/library/1k1skd40.aspx

Following agent-j's answer, you can add the DateTimeStyles to DateTime.Parse(...)
date= "Wed, 16 Oct 2013 00:00:00 GMT";` // from javascript.getUTCString()
DateTime.Parse(date, CultureInfo.InvariantCulture, DateTimeStyles.AdjustToUniversal));