What could cause "ServiceException: Operation Failed"?

[peterraeves]

I'm having the below exception, what might be the cause?

We have an itil user, that is allowed to update his own records. He is allowed to update the state through webservices (!gs.isInteractive()), and it works when using the REST API Explorer. When he does it on his own, he does not get any ACL errors, and everything went seemingly fine, but the record is not updated and in the ServiceNow logs, we get the following error:

Operation Failed: com.glide.rest.domain.ServiceException: Operation Failed: com.glide.rest.util.GlideRecordValidator.checkForErrorOrThrowDefaultError(GlideRecordValidator.java:38)<br/>com.glide.rest.util.GlideRecordHandler.updateRecord(GlideRecordHandler.java:152)<br/>com.glide.rest.service.table.TableAPIService.modify(TableAPIService.java:221)<br/>com.glide.rest.service.table.TableAPIService.replace(TableAPIService.java:199)<br/>com.glide.rest.service.table.TableAPIV2Service.replace(TableAPIV2Service.java:96)<br/>sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)<br/>sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)<br/>sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)<br/>java.lang.reflect.Method.invoke(Method.java:597)<br/>com.glide.rest.handler.impl.ServiceHandlerImpl.invokeService(ServiceHandlerImpl.java:41)<br/>com.glide.rest.processors.RESTAPIProcessor.process(RESTAPIProcessor.java:217)<br/>com.glide.processors.AProcessor.runProcessor(AProcessor.java:409)<br/>com.glide.processors.AProcessor.processTransaction(AProcessor.java:183)<br/>com.glide.processors.ProcessorRegistry.process(ProcessorRegistry.java:165)<br/>com.glide.ui.GlideServletTransaction.process(GlideServletTransaction.java:32)<br/>com.glide.sys.ServletTransaction.run(ServletTransaction.java:34)<br/>java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)<br/>java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)<br/>java.lang.Thread.run(Thread.java:682)<br/>

FYI: This works completely fine when we give him admin rights

[THEDLA Venkata]

We are also facing the same issue, It would be great any one address this.