Unable to find an entry point named 'GeoIPValidate' in DLL 'MEAISO.DLL' error when logging into web mail client.


When logging into the MailEnable web mail client the following .NET error is returned:

Server Error in '/' Application.

Unable to find an entry point named 'GeoIPValidate' in DLL 'MEAISO.DLL'.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.EntryPointNotFoundException: Unable to find an entry point named 'GeoIPValidate' in DLL 'MEAISO.DLL'.

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: 

[EntryPointNotFoundException: Unable to find an entry point named 'GeoIPValidate' in DLL 'MEAISO.DLL'.]
MailEnable.Administration.SystemOption.GeoIPValidate(String& IPAddress, IGeoIPData& GeoData) +0
MailEnable.Administration.SystemOption.GetCountryCodeByIPAddress(String IPAddress) +48
MailEnable.Clients.WebMail.Mondo.login.xad7c5749486f1b4d(String xb693f12cd8e89729, String x63cc9922b78e9f75, String x037139f144ea18d2, String xd6b1c9f28590f864, Boolean x437f654e0237af6e) +1155
MailEnable.Clients.WebMail.Mondo.login.x65786cb9e5cd1242() +627
MailEnable.Clients.WebMail.Mondo.login.xde97676d01739ced(Object xe0292b9ed559da7d, EventArgs xfbf34718e704c6bc) +2872
System.Web.UI.Control.OnLoad(EventArgs e) +132
System.Web.UI.Control.LoadRecursive() +66
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2428


The cause of the .NET error is that there is an old version of the MEASIO.DLL present on the server which is being used by the web mail client.


  • Restart the server to ensure that the environment variable paths have taken effect to find the correct DLL.
  • If this does not resolve the error, then search on all drives for the file MEAISO.DLL. There should only be two copies of this file on the server. One in the Mail Enable\bin directory and the other in the Mail Enable\bin64 directory. If you have reinstalled the software to another path there may be older DLLs that are being access. To delete older DLLs that are in use, run the mestop.bat file from the Mail Enable\bin directory (which stops all the mail services), delete the files and then run the mestart.bat file from the Mail Enable\bin directory. You may need to run these bat files as an administrator.



Product:MailEnable (All Versions)
Class:PRB: Product Problem or Issue
Revised:Monday, July 4, 2016