WebDav PROPPATCH method status HTTP/1.1 424 Failed Dependency -

i trying access , modify properties 'creationdate' , 'lastmodified' of file have uploaded webdav url. getting response 'http/1.1 424 failed dependency' interpret 'the request failed due failure of previous request' according https://tools.ietf.org/html/rfc4918.

i lost previous request failing here, when run code don't error on it. here code:

fileinfo^ myfi=gcnew fileinfo(myfilepath); string^ mytime=myfi->lastwritetimeutc.tofiletimeutc().tostring(); string^ strbody = "<?xml version=\"1.0\"?>"             + "<d:propertyupdate xmlns:d=\"dav:\">"             + "<d:set>"             + "<d:prop>"             + "<creationdate>" + myfi->creationtimeutc.tofiletimeutc().tostring() + "</creationdate>"             + "</d:prop>"             + "<d:prop>"             + "<lastmodified>" + mytime + "</lastmodified>"             + "</d:prop>"             + "</d:set>"             + "</d:propertyupdate>";  array<byte>^ mybytes= encoding::utf8->getbytes(strbody);  string^ responseresult=""; string^ filename= myfi->name; system::net::httpwebrequest^ httpputrequest = (system::net::httpwebrequest^)system::net::webrequest::create(this->myurl + destinationpath+ "/" + filename);     httpputrequest->credentials = gcnew networkcredential(this->myusername, this->mypassword);     httpputrequest->preauthenticate = true;     httpputrequest->method = l"proppatch"; httpputrequest->contenttype = "text/xml"; httpputrequest->contentlength = mybytes->length; stream^ requeststream = httpputrequest->getrequeststream(); requeststream->write(mybytes,0,mybytes->length); requeststream->close();  httpwebresponse^ httpputresponse = (httpwebresponse^)httpputrequest->getresponse(); responseresult=httpputresponse->statusdescription; httpstatuscode mycode=httpputresponse->statuscode; stream^ myresponse=httpputresponse->getresponsestream(); streamreader^ myr=gcnew streamreader(myresponse); string^ res=myr->readtoend(); 

i have tried 1 property , have same response.

any advise, please?

it's important echo entire response. failed dependency emitted in following case:

1. you doing proppatch update more 1 property
2. one of properties fails (for example 403 forbidden)
3. the other properties automatically 424 failed dependency, because propatch must either entirely succeed, or entirely fail.

my guess server not allow update 1 or more of properties. {dav:}lastmodified in particular in general protected, , read-only property never allowed change. depends on server if or not allow that, in general should fail.