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ODBC -- Call Failed

Hello Experts,

I have a frontend in Access 2010 and Backend in SQL 2008 Express R2. Even though Access is 2010 the rest of Office is 2007.

Sometimes I get a series of ODBC errors, like Call Failed or Update Failed.

The computer where SQL is installed on is Windows 7 Pro and I have read that in Win 7 there are limited numbers of TCP/IP connections. Is this true, and can this be causing the ODBC errors?

If this is the case, I guess I have no choice than to upgrade the "server" to actual server, like Windows 2008, but before I do is there a way to look at how many  TCP/IP connections are actually open? Also what is the TCP/IP limitations of Win 7?

I assume that Win 2008 does not have such limits, correct?

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David Johnson, CDSimple Geek from the '70s
Distinguished Expert 2019

20 connection limit in Windows Client Operating Systems.
Server depends upon version. Web and Foundation editions have connection limits (50) while Standard, Enterprise, and Data center do not.
APD TorontoSoftware Developer


Is there a way to check the number of connections at any given time?
Most Valuable Expert 2014
Grab a copy of the Sysinternals TCPView v3.05 from MS.

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