Oracle.ManagedDataAccess and ORA-01017: invalid username/password; logon denied

Based on Jeff's answer (10/31/2014)...

The registry setting can be set by GPO to only allow FIPS compliant algorithms. Setting this to 0 as indicated may be a violation of some security policies and get overwritten by the GPO. This registry setting controls more than just IIS or ASP.NET.

There is another way that is specific to .NET and may work at the application level. This is much easier to justify compared to modifying the settings of the whole server.

Application specific method:

In your Web.config or App.config file, add the following setting:

<configuration> <!-- Will already be there -->
  <runtime>
    <enforceFIPSPolicy enabled="false"/>
  </runtime>
...  the rest of your .config

If I remember correctly, this must be at the beginning of your config file.

All .NET application method:

Place the setting above in the machine.config file. There will be one for each .NET version and architecture (64 bit/32 bit). There will already be a element, so put the element inside it.

I have been struggling with this same issue for a couple of weeks and finally have a resolution. I had to disable the FIPS security policy, try setting this key:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\FipsAlgorithmPolicy] "Enabled"=dword:00000000

to zero, it worked perfectly for me

I was following your thread your blank password issue eventually pointed me here:

https://community.oracle.com/thread/2557592?start=30&tstart=0