Have you made sure all previous installations of MT4 are completely removed from your PC before you install the new one ?

Yes SDC. I unistall with the function eliminate all. I made sure the folder MT4 was deleted, and I checked, any time I inistall, that there is not archive in the virtualStore secret folder.

Today I tried to clean with ccleaner, but neither worked.

I thing is something in the Pc, because I probed installing MT4 from others brokers, and neither worked. Then, is not the broker archive, I guess.

but what can be?

Don't install in personal folders as they have specific access privileges!

Rather create a new folder/directory at the root of your data drive, such as "D:\MetaTrader" and give it full privileges.

Then install MT in a subfolder of "D:\MetaTrader" such as "D:\MetaTrader\MT4\Broker1\Demo-123456\" or "D:\MetaTrader\MT5\Broker2\Live-654321\".

Later if you use different brokers and accounts, they will all be nicely stored and structured under that single "D:\MetaTrader" and will make backing all the data easy.

I agree with you it is something else, I think we can discount installation directory problems. In my opinion Installing in Program Files is fine anyway. I am starting to wonder if this might be a 64bit OS vs 32bit application problem. Install it again in the default installation directory, then go the terminal.exe > right click on it > Properties > Compatability > Check the box "Run this program in compatability mode for" and choose "Windows XP service pack 2" in the list then try to run it.

I do not think it to be a 64bit OS problem. All my installations are on 64bit machines on Windows 7 or Windows 2008 R2 Server and I have never had any problems.

However, as I stated before, on these operating systems, since privileges on "Personal Folders" and also in "Program Files" are different to what it was previously on Windows XP. That was the reasoning behind installing MT4 under a separate director/folder and not under the Program Files as a means of future access.

However, for a one time installation where one does not have multiple installations, brokers and accounts, yes it does function properly under the "Program Files" folder under 64bit OS without any problem.

There is no need even to touch the "Compatibility Mode" of the application. It runs just fine without any required alteration by the user on 64bit OS.

Hmmm ok well in that case I can't think of anything else that would cause the problem. Trader 201 said he had that incompatable applicatiuon error if it isnt a 64bit issue what could it mean ?

His/her Windows installation is screwed up . . . he/she needs to find out what is causing the issue, I gave a pointer but seem to have been ignored.

Hello. I was in festive days in my city.

"SDC Have you made sure all previous installations of MT4 are completely removed from your PC before you install the new one ?"

I am revising, any time I unistalled MT4, the program files and secret folders, that there is any MT4 folder.

Is another location whare can save Mt4 archive?

FMIC

"Don't install in personal folders as they have specific access privileges!

Rather create a new folder/directory at the root of your data drive, such as "D:\MetaTrader" and give it full privileges.

Then install MT in a subfolder of "D:\MetaTrader" such as "D:\MetaTrader\MT4\Broker1\Demo-123456\" or "D:\MetaTrader\MT5\Broker2\Live-654321\".

Later if you use different brokers and accounts, they will all be nicely stored and structured under that single "D:\MetaTrader" and will make backing all the data easy".

I will do that, and see what happen.

SDC "...Install it again in the default installation directory, then go the terminal.exe > right click on it > Properties > Compatability > Check the box "Run this program in compatability mode for" and choose "Windows XP service pack 2" in the list then try to run it."

did not work

SDC

"His/her Windows installation is screwed up . . . he/she needs to find out what is causing the issue, I gave a pointer but seem to have been ignored."

What do you meant? I'm trying anything new. I am interested in correct this problem.

You said you did it already . . .

What RaptorUK (not SDC) suggested was that you use a Process Monitor, such as "Microsoft's System Internals Process Monitor" <http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx> or in the very least, the built-in "Windows Task Manager", to analyse your PC and the process handling of MT4 and see if there is not anything causing the problem, such as Malware.

However, I am of the opinion, that if you do not know what he meant, that you do not have the technical knowledge to be able to detect or even correct the problem yourself. So, my suggestion is, that you have a qualified technician or someone else knowledgeable take a look at your PC in order to find the problem.

In other words, your difficulties are not related to MQL4 or MT4 and are more related to Operating System difficulties and do not really belong on this forum. Until, you can resolve your PC issues you will not be able to move onto the next step with the use of MT4 or MQL4 coding.

Everyone else is able to install and run MT4 even on 64-bit OS's (and even on Linux machines running "Wine"), so it is not really a MT4 bug issue. Something must be "screwed up" on your PC!

So take RaptorUK's advice, and first sort out you PC!