Changed password hashing to try SHA-1 first and if that doesn't work then try SHA-0. This should allow shard owners to chose either SHA-1 or SHA-0 for their password hash without interfering with other shards. And allow them to change their password hash without requiring everyone to reset their passwords.

This also allows for future expansion of new hash techniques to be added, of course the more hash techniques added the more delay at login for the lowest on the totem pole.
I have tested this against the MOULa shard that uses SHA-0 and it works, there is a slight flash of the "Connecting dialog" as it re-tries sending the login but if the user saves the password, there is no flash and no delay.

MOULOpenSourceClientPlugin/Plasma20/Sources/Plasma/Apps/plClient/winmain.cpp

@@ -206,7 +206,7 @@ bool GetDisksProperty(HANDLE hDevice, PSTORAGE_DEVICE_DESCRIPTOR pDevDesc);
 void GetOldCryptKey(UInt32* cryptKey, unsigned size);
 void GetCryptKey(UInt32* cryptKey, unsigned size);
 static void SaveUserPass (char *username, char *password, ShaDigest *pNamePassHash, bool remember_password,
-								  bool fromGT);
+								  int whichHash);
 static void LoadUserPass (const wchar *accountName, char *username, ShaDigest *pNamePassHash, bool *pRemember,
 								  bool fromGT, int *pFocus);
 static void AuthFailedStrings (ENetError authError, bool fromGT,
@@ -322,11 +322,25 @@ static bool TGRunLoginDialog (const wchar *accountName, bool fromGT)
 		if (Remember[0] == 'y')
 		  bRemember = true;
 
-		SaveUserPass (Username, Password, &NamePassHash, bRemember, fromGT);
+		// cycle through the hash types until we find one that matches or errors out
+		int whichHash = 1;
+		ENetError auth;
+		bool cancelled;
+		while (whichHash >= 0 )
+		{
+			SaveUserPass (Username, Password, &NamePassHash, bRemember, whichHash);
 
 			// Do login & see if it failed
-		ENetError auth;
+			cancelled = AuthenticateNetClientComm(&auth, NULL);
-		bool cancelled = AuthenticateNetClientComm(&auth, NULL);
+			// if the password was successful then go to the end processing
+			if (IS_NET_SUCCESS(auth) && !cancelled)
+				break;
+			// if it was cancelled or any error other than wrong password then go to end processing
+			if (cancelled || auth != kNetErrAuthenticationFailed)
+				break;
+			// otherwise try then next Hash type
+			whichHash--;
+		}
 
 		if (IS_NET_SUCCESS (auth) && !cancelled)
 			break;
@@ -1081,7 +1095,7 @@ BOOL CALLBACK UruTOSDialogProc( HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM l
 }
 
 static void SaveUserPass (char *username, char *password, ShaDigest *pNamePassHash, bool remember_password,
-						  bool fromGT)
+						  int whichHash)
 {
 	UInt32 cryptKey[4];
 	ZeroMemory(cryptKey, sizeof(cryptKey));
@@ -1097,7 +1111,30 @@ static void SaveUserPass (char *username, char *password, ShaDigest *pNamePassHa
 	if (StrCmp(password, FAKE_PASS_STRING) != 0)
 	{
 		StrToUnicode(wpassword, password, arrsize(wpassword));
+
+		switch( whichHash )
+		{
+			case 1:
+				CryptDigest(
+					kCryptSha1,
+					pNamePassHash,
+					StrLen(password) * sizeof(password[0]),
+					password
+					);
+
+				if (IsMachineLittleEndian()) {
+					pNamePassHash->data[0] = ToBigEndian(pNamePassHash->data[0]);
+					pNamePassHash->data[1] = ToBigEndian(pNamePassHash->data[1]);
+					pNamePassHash->data[2] = ToBigEndian(pNamePassHash->data[2]);
+					pNamePassHash->data[3] = ToBigEndian(pNamePassHash->data[3]);
+					pNamePassHash->data[4] = ToBigEndian(pNamePassHash->data[4]);
+				}
+				break;
+
+			default:
 				CryptHashPassword(wusername, wpassword, pNamePassHash);
+				break;
+		}
 	}
 
 	NetCommSetAccountUsernamePassword(wusername, *pNamePassHash);
@@ -1106,7 +1143,6 @@ static void SaveUserPass (char *username, char *password, ShaDigest *pNamePassHa
 	else
 		NetCommSetAuthTokenAndOS(nil, L"win");
 
-	if (!fromGT) {
 	wchar fileAndPath[MAX_PATH];
 	PathGetInitDirectory(fileAndPath, arrsize(fileAndPath));
 	PathAddFilename(fileAndPath, fileAndPath, L"login.dat", arrsize(fileAndPath));
@@ -1128,7 +1164,6 @@ static void SaveUserPass (char *username, char *password, ShaDigest *pNamePassHa
 		stream->Close();
 		delete stream;
 	}
-	}
 }
 
 
@@ -1418,11 +1453,25 @@ BOOL CALLBACK UruLoginDialogProc( HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM
 					GetDlgItemText(hwndDlg, IDC_URULOGIN_PASSWORD, password, kMaxPasswordLength);
 					remember_password = (IsDlgButtonChecked(hwndDlg, IDC_URULOGIN_REMEMBERPASS) == BST_CHECKED);
 
-					SaveUserPass (username, password, &namePassHash, remember_password, loginParam->fromGT);
+					// cycle through the hash types until we find one that matches or errors out
-
+					int whichHash = 1;
 					LoginDialogParam loginParam;
+					bool cancelled;
+					while (whichHash >= 0 )
+					{
+						SaveUserPass (username, password, &namePassHash, remember_password, whichHash);
+
 						MemSet(&loginParam, 0, sizeof(loginParam));
-					bool cancelled = AuthenticateNetClientComm(&loginParam.authError, hwndDlg);
+						cancelled = AuthenticateNetClientComm(&loginParam.authError, hwndDlg);
+						// if the password was successful then go to the end processing
+						if (IS_NET_SUCCESS(loginParam.authError) && !cancelled)
+							break;
+						// if it was cancelled or any error other than wrong password then go to end processing
+						if (cancelled || loginParam.authError != kNetErrAuthenticationFailed)
+							break;
+						// otherwise try then next Hash type
+						whichHash--;
+					}
 
 					if (IS_NET_SUCCESS(loginParam.authError) && !cancelled)
 						EndDialog(hwndDlg, ok);