Network adapater constantly disconnects

I have a VM that was originally created with VMWare Fusion 7. About a month ago I migrated to Parallels because Fusion's performance with Yosemite was atrocious (fans constantly on high, CPU 100%, etc etc). Parallels is much better, however, the network card in Windows keeps losing connectivity and I must constantly disable/re-enable it. After doing so, it's fine for another 5min-hr-4hrs ... all random but will always disconnect eventually.

The Parallels VM was created by converting the Fusion image. I'm unsure if this is why I may be having this issue.

Host: Mac OS X Yosemite 10.10.3
Guest: Windows 8.1

 

Hi Daniel,
Please try re-installing Parallels Tools, refer http://kb.parallels.com/4841. Also check which network mode is selected under Virtual Machine Configure, refer http://kb.parallels.com/4948

 

Thanks Dhruba,
I've tried all of that previously. I've removed all network adapters from the VM's settings. The adapter is using the shared network mode.

 

Hi Daniel, Please follow the steps suggested below:
1. Go to Control panel > Device Manger > Remove all drivers under network adapter,
2. Go to Control panel > programs and features > Un install VMWare Fusion Tools if they are installed,
3. Restart the Virtual Machine and check if the issue still persisting.

 

So far, so good after removing all network adapter drivers. It been connected for about an hour. now Will continue to check and report back here.

EDIT
Nope ... just disconnected after using the internet on the Windows guest.

 

Hi Daniel, Please follow the steps suggested at http://kb.parallels.com/8978 and check if the issue still persisting.

 

Hi,
I'd appreciate a remote support session to investigate the problem.
If you agree, then send me please your email address and your time frame for the session via forum's private message and make a snapshot of the VM when you see the issue next time.
(I'll be available since 12 may, working days, 11.00-17.00 UTC)

 

Sorry Elric, I just got back into town. I would really appreciate your help on this. I'll message you shortly to set up a session.

 

@Elric, I just wanted to catch you up on the status of this issue since we last spoke. The changes we made using sfc /scannow did not correct the issue unfortunately. Yesterday the issue became so frustrating (disconnecting every few minutes) that I was about to reformat the VM. At a last attempt I looked at Parallel's hardware settings for the VM and noticed I could choose a different network adapter than Intel Pro/1000 MT.
The steps I took to work around these network issues were:

1. Uninstall (using Device Manager) all network adapters/drivers in Windows.
2. Shut down the VM
3. Change the VM's NIC Type to Realtek
4. Start the VM

For the moment, it seems this new network card has corrected my issues. Although my assumption is that something in the conversion process from a Fusion 7 VM to a Parallels 10 VM corrupted either a Windows network driver or the Intel Pro/1000 MT driver. I would assume that if Parallel's Intel driver was broken there would be posts all over these forums with customers having this issue but it seems this is scoped to a converted VM. Maybe even something I had done with the network settings in Fusion are the culprit.

In any case, thanks for taking the time to help diagnose this. If the problem comes back I'll open a ticket but more likely, I'll just reformat.

 

As far as I remember Parallels doesn't install any drivers for Intel Pro/1000 MT (or may be they are preinstalled in the VM BIOS, or smth like that). The idea is to let users connect to the network even if Parallels Tools are not installed. I guess, this is mostly required when installing Linux VMs, as most of Linux distributives suggest downloading all the possible updates when installing OS. Also, it's useful when installing Windows VMs, as since Win8 they suggest login to MS account. So, probably Fusion tools make any changes in the native Windows drivers. Realtek drivers go with the Parallels Tools (you probably noticed the name of the card in the Device Manager is Parallels Network Adapter). If Realtek works, then better stay with the Realtek adapter. If you uninstall Parallels Tools, network may be down.

 

So glad to have found this post. All my VMs were suffering from frequent network disconnects. Now, after changing the VM's NIC Type to Realtek, as described, it looks like the problem has well and truly gone away. Many thanks for sharing your solution to a really annoying scenario.