Gateway and scheduled refresh problems

HI Everyone first time on the forum, hoping someone can assist me.  I have a powerBI desktop file on my PC. It is accessible by multiple people via the online platform. I have a personal gateway installed with scheudled refresh to ensure the data is up to date. Has been working fine until today.  I was doing a check to ensure that all reports were updating ok and i noticed that one hadn't. The scheduled refresh failed - "We reached the data gateway, but the gateway can't access the on-premises data source". I am now only realising that the failures go back at least as far as the the 13th August. Did something get updated in August from POWER BI? Anyway - after trying a few things i decided to uninstall and reinstall the personal gateway. However, when i now install and enter my BI log in credentials it shows me the error below. Error generating an asymmetric key. Exception message: Key not valid for use in specified state. Key not valid for use in specified state. Server stack trace: at System.ServiceModel.Channels.ServiceChannel.ThrowIfFaultUnderstood(Message reply, MessageFault fault, String action, MessageVersion version, FaultConverter faultConverter) at System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc) at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation) at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message) Exception rethrown at [0]: at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg) at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type) at Microsoft.PowerBI.DataMovement.Pipeline.ConfigurationContracts.IGatewayConfigurationService.GenerateAsymmetricKey() at Microsoft.PowerBI.DataMovement.Pipeline.GatewayClient.GatewayConfigurationClient.GenerateAsymmetricKey()An ExceptionDetail, likely created by IncludeExceptionDetailInFaults=true, whose value is: System.Security.Cryptography.CryptographicException: Key not valid for use in specified state. at System.Security.Cryptography.Utils.CreateProvHandle(CspParameters parameters, Boolean randomKeyContainer) at System.Security.Cryptography.Utils.GetKeyPairHelper(CspAlgorithmType keyType, CspParameters parameters, Boolean randomKeyContainer, Int32 dwKeySize, SafeProvHandle& safeProvHandle, SafeKeyHandle& safeKeyHandle) at System.Security.Cryptography.RSACryptoServiceProvider.GetKeyPair() at System.Security.Cryptography.RSACryptoServiceProvider..ctor(Int32 dwKeySize, CspParameters parameters, Boolean useDefaultKeySize) at Microsoft.PowerBI.DataMovement.Pipeline.GatewayServiceHost.AsymmetricKeyGenerator.ProduceAsymmetricKey(String containerName, Boolean cleanUpOldKeys, Int32 rsaKeySize) at Microsoft.PowerBI.DataMovement.Pipeline.GatewayPipelineTelemetry.PipelineTelemetryService.ExecuteInActivity[T](PipelineActivityType pipelineActivityType, Func`1 action) at SyncInvokeGenerateAsymmetricKey(Object , Object[] , Object[] ) at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs) at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc& rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc& rpc) at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage11(MessageRpc& rpc) at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet) grateful for any assistance at all. thanks in advance