Thanks sassypachuco editing the gns3.net file helps by pointing to different port than 11xxxx values.

After upgrading to 0.8.4 yesterday I faced this issue and I was unable to load any old topologies created/used with 0.8.3.

I could solve it by doing two things:

First change the Base UDP value to 50000, which I set and used in 0.8.3 before. The upgrade seems to override this old value and it's back to 10000.

The second thing is to check the UDP values ('udp = xxxxx') in the NET file. Renumbering those values starting with 50000 (in my case) and increasing it by 100 for each section in the NET file helped to solve the issue luckily.

Sounds like you've got some other apps using ports around 10000 - if so you've gone about solving the problem the correct way. Curious that 0.8.4 didn't honour the old UDP=50000 parts of your old config though.

_________________
RedNectar
http://rednectar.net
@rednectarchris
GNS3 WorkBench-a VMware image of Ubuntu with GNS3 and VPCS installed and a collection of exercises/labs

For those still having issues. I fixed mine by changing the "BaseUPD to 50000" then going to the topology i was trying to open, right clicking and editing. And manually changing to "upd = 50000". All while running in administrator mode.

This setting will only apply to NEW topologies created after you apply the setting. It will not change existing topologies. You can tell what ports an existing topology uses by:
a) Load the topology
b) Issue a show run command int he GNS3 console window

GNS3 has no facility change the base UDP port of an existing configuration. Perhaps you should put in a feature request here to add an Apply to current configuration option in the GNS3 Preferences, Dynamips settings. It would need to be applied while all routers were stopped, and may even require to re-load your configuration again, but would be a useful feature. I would certainly support it.

So at the moment, the only way to change exiting topologies is to edit the topology.net file by hand.

_________________
RedNectar
http://rednectar.net
@rednectarchris
GNS3 WorkBench-a VMware image of Ubuntu with GNS3 and VPCS installed and a collection of exercises/labs

I removed s0/0 = NIO_udp:11101:127.0.0.1:*** which i didn't need anyways! It works for me

Problem solved after changing BASE UDP to 50000 and Changing udp ports inside the .net file by increment of 100 and also changing the image and working directories paths and changing "localhost" to 127.0.0.1 ...Thanks everyone

Hi
Does any one try to exit antivirus ?
I got the same problem 206 unable , and already change the UDP 10000 to 10001 , but still got the same error.
But when I exit the 360 antivirus , I can open this GNS project without any problem.
It works for me now .

Guys,

Hope this still helps, under the Edit > IOS images and hypervisors > External hypervisors tab
You will have to use a different Port, Base UDP port, Base console, Base AUX
Click SAVE
Click SAVE again
Ex:
127.0.0.1 : 7700 : 10701
127.0.0.1 : 7701 : 10801
127.0.0.1 : 7702 : 10901
Delete other ports already defined there that you have not yourself created.

Now this is the tricky part:
Edit the topology.net file using any text editor

Change the Port, Base UDP port, Base console, Base AUX according to what you have defined in the External hypervisors tab (Above), you can increment by one per PORT

Ex:
autostart = False
version = 0.8.4
[127.0.0.1:7700]
workingdir = working
udp = 10701
[[7200]]
image = /IOS/c7200-adventerprisek9-mz.152-4.S3.image
mmap = False
sparsemem = True
[[ROUTER R5-PE]]
console = 2701
aux = 2701
cnfg = configs/R5-PE.cfg
slot0 = C7200-IO-GE-E
g0/0 = CE2 g0/0
slot4 = PA-GE
g4/0 = R4 g4/0
x = 87.0
y = -123.0
z = 1.0
hx = 11.5
hy = 20.0
[[ROUTER CE2]]
console = 2702
aux = 2702
cnfg = configs/CE2.cfg
slot0 = C7200-IO-GE-E
g0/0 = R5-PE g0/0
slot1 = PA-FE-TX
f1/0 = CORE-SW2 f1/0
x = 96.0
y = 66.0
z = 1.0
hx = 19.5
hy = 16.0
[[ROUTER CE1]]
console = 2703
aux = 2703
cnfg = configs/CE1.cfg
slot0 = C7200-IO-GE-E
g0/0 = R1-PE g0/0
slot1 = PA-FE-TX
f1/0 = CORE-SW1 f1/0
x = -540.0
y = 64.0
z = 1.0
hx = 20.5
hy = 19.0
[127.0.0.1:7701]
workingdir = working
udp = 10801
[[3725]]
image = /IOS/c3725-adventerprisek9-mz.124-25d.image
ram = 128
mmap = False
sparsemem = True
[[ROUTER CORE-SW1]]
model = 3725
console = 2721
aux = 2721
cnfg = configs/CORE-SW1.cfg
slot1 = NM-1FE-TX
f1/0 = CE1 f1/0
slot2 = NM-16ESW
f2/1 = CORE-SW2 f2/1
f2/2 = CORE-SW2 f2/2
x = -539.0
y = 243.0
z = 1.0
hx = -9.5
hy = 17.0
[[ROUTER CORE-SW2]]
model = 3725
console = 2722
aux = 2722
cnfg = configs/CORE-SW2.cfg
slot1 = NM-1FE-TX
f1/0 = CE2 f1/0
slot2 = NM-16ESW
f2/1 = CORE-SW1 f2/1
f2/2 = CORE-SW1 f2/2
x = 102.0
y = 237.0
z = 1.0
hx = -7.5
hy = 16.0
[127.0.0.1:7702]
workingdir = working
udp = 10901
[[7200]]
image = /IOS/c7200-adventerprisek9-mz.152-4.S3.image
mmap = False
sparsemem = True
[[ROUTER R4]]
console = 2741
aux = 2741
cnfg = configs/R4.cfg
slot3 = PA-GE
g3/0 = R3 g3/0
slot4 = PA-GE
g4/0 = R5-PE g4/0
x = 6.0
y = -300.0
z = 1.0
[[ROUTER R2]]
console = 2742
aux = 2742
cnfg = configs/R2.cfg
slot1 = PA-GE
g1/0 = R1-PE g1/0
slot2 = PA-GE
g2/0 = R3 g2/0
x = -448.0
y = -296.0
z = 1.0
[[ROUTER R3]]
console = 2743
aux = 2743
cnfg = configs/R3.cfg
slot2 = PA-GE
g2/0 = R2 g2/0
slot3 = PA-GE
g3/0 = R4 g3/0
x = -206.0
y = -299.0
z = 1.0
[[ROUTER R1-PE]]
console = 2744
aux = 2744
cnfg = configs/R1-PE.cfg
slot0 = C7200-IO-GE-E
g0/0 = CE1 g0/0
slot1 = PA-GE
g1/0 = R2 g1/0
x = -539.0
y = -115.0
z = 1.0
hx = 9.5
hy = 20.0
[GNS3-DATA]
configs = configs
workdir = working

Click save on the text file