Problem Description: SharePoint shows network break/unknown error very frequently (on average 3 on 5 days in week. Client end up trying the file upload 4-5 times to do it (each iteration being of 10 min. each)

Error Message: Server request timed out. Please try again or the network connection with the server has been lost. Please try again.

Troubleshooting done:

ü  Checked how big the file is? It’s around 25 MB. We have upload limit of 100 MB in our farm.

ü  What is the name of the Library name?

ü  How is client trying to upload the file? Client was using both upload document” or “upload multiple documents” option for file upload on the site.

ü  Tried adding a entry in the host file and checked and no go.

ü  Removed the user from all people still the user gets all the options and is able to get to the option of upload, did not find the user in any DL.

ü  Added the use as a site collection admin still no go.

ü  Cleared the cache still the same.

ü  Added back the permissions removed of the user.

ü  Ran the office diags no go.

ü  It works from a different machine.

ü  On the other machine on the first document library it works always. On the second library it works sometimes.

ü  Cleaned the temp folder which was 680 MB and could upload the file for the first time, second, the transfer rate he experience in upload is about 20 kbps whereas other colleagues are able to transfer files to SharePoint at about 150+ kbps.

ü  Suggested client that transfer rate could also depend upon the network speed or the internet bandwidth. And local LAN support could assist him better in increasing the transfer rate.

ü  Tried uploading the 14 MB file from ‘Upload multiple file’ option. And waited for 10 Min and get error message ‘The network connection with the server has been lost. Please try again.’

ü  Noticed while uploading the file the transfer rate of the upload was 40 kbps, and client did notice the upload transfer rate as 150 kbps for his other colleagues.

ü  Network card is configures to run on 100 mbps.

ü  Tried to upload a little less sized file of 9 MB on another site. It also did take same amount of time.

ü  Working on another machine for the client doesn’t take much time to upload the file for one site.

ü  It seems it is related to the network bandwidth issue.

Resolution: Changing the LAN settings to be 100 mbps full duplex it makes the things working fine. It was set to 10 mbps something. To change the settings go to

My Computer (right click properties)> Hardware > Device Manager > LAN settings.

Applies to: SharePoint 2007, SharePoint Server 2010.