Hi, Nearly finished my virtual COM port but one outstanding issue - MsComm.ocx! Writing/IoCtl work fine; reading works fine under everything except Mscomm - read queue in driver is manual but whenever.Input method (aka read) is invoked on MsComm I get COM Exception 0x800A1F54 (under a.net app) or Run Time Error 8020 (under VB6 app) According to MS KB 318784 'MsComm does not expect the ReadFile method to return ERROR_IO_PENDING; strange, I'm completing the read request as fxRequest->CompleteWithInformation ( S_OK, bytesRead ) Any ideas as to what to do? >According to MS KB 318784 'MsComm does not expect the ReadFile method = to return=20 >ERROR_IO_PENDING;=20 Correct. A well-known bug in MsComm. Autocad 2000 Auf Windows 8 Installieren Rolladenschnur there. ocx. >strange, I'm completing the read request as = fxRequest->CompleteWithInformation Sorry, but KMDF has a queue above your code, which pends the IRP. Do all work in InCallerContext callback, or abandon KMDF at all, or live = with bug in MsComm.ocx (who on Earth uses this ancient stuff in 2010?) --=20 Maxim S.

Shatskih Windows DDK MVP xxxxx@storagecraft.com http://www.storagecraft.com. Maxim >According to MS KB 318784 'MsComm does not expect the ReadFile method to return >ERROR_IO_PENDING; Correct. A well-known bug in MsComm.ocx.

Been there, met it before, got around it in WDM:-)! >strange, I'm completing the read request as fxRequest->Download Game Plant Vs Zombie 1 Gratis Untuk Pc more. CompleteWithInformation Sorry, but KMDF has a queue above your code, which pends the IRP. Hmmm, I'm using UMDF Do all work in InCallerContext callback, or abandon KMDF at all, or live with bug in MsComm.ocx (who on Earth uses this ancient stuff in 2010? Doves The Last Broadcast Rar here. ) Don't blame me, blame my client (who's still living in the past) More proper info - may help??? Write command which replies First read (of 1 byte) fails 8020, now 1 byte queued 2nd read (of 1 byte) fails 8020, now 0 bytes queued 3rd read (of 1 byte) doesn't fail and appears to read the Thanks Adrian. You don't have to abandon instead, but you do have to handle reads speciall= y so that mscomm32.ocx does not die. D sent from a phpne with no keynoard -----Original Message----- From: xxxxx@villasoft.co.uk Sent: May 31, 2010 10:29 AM To: Windows System Software Devs Interest List Subject: RE:[ntdev] Virtual COM Port driver / MSComm Maxim >According to MS KB 318784 'MsComm does not expect the ReadFile method to = return >ERROR_IO_PENDING; Correct.