fotodamaris wrote

just to test try
Wireless Settings
Mode: BG Mixed
Channel Width: 20 MHZ

Ok trying that. Had it in BGN Mixed mode until now. Currently works, but there also were periods of time were it kept working with bgn mixed mode for a while. I will return if the error keeps occurring.

Still - thanks for the fast answer.

Intel N7260 wireless adapter have a very poor compatibility with many routers . You can google it , anyway I have throw it away!

After a few days of testing I think it´s safe to say that solved the problem!
Thanks!

Same problem. My company just issued new Lenovo Laptops with the Intel 7260 wireless chipset. Same thing was happening to a few of us with TP-Link TL-WR841 routers.
Turns out that this is an issue with running the laptop in battery mode.

When you're using battery,Power Save Polling (PSP) causes connection issues with access points or with routers
Symptom(s):
The following symptoms can happen if a Wi-Fi access point (AP) or Wi-Fi router does not support the power save polling (PSP) feature:
•Intermittent loss of Wi-Fi connection
•Inability to initiate a Wi-Fi connection
•Poor Wi-Fi connection data performance
Using battery power can cause these symptoms to be noticeable.

Cause:
PSP mode is a feature that provides extended battery life for laptop computers. The mode requires coordination between the AP or router and the Wi-Fi adapter. Intel has discovered that some APs or routers may not implement the feature correctly or completely.

Solution:
1.Manually put the Wi-Fi adapter into continuously aware mode (CAM). This disables the PSP feature. Set CAM by using one of the following methods:
•Intel PROSet/Wireless WiFi Connection Utility
•Network control panel applet (NCPA)
Note:Using this way can cause your Bluetooth device to not receive signals. Contact your computer manufacturer for more information.

2.Disable U-APSD support
Go to Control Panel >> Hardware and Sound >> Device Manager >> Network Adapters >> Intel Dual Band Wireless-AC 7260 >> right click to select the "Properties">>Advance>>Diasble U-APSD support >>Click OK button

The following is steps for setting CAM:

Set CAM using Intel PROSet/Wireless WiFi Connection Utility

From the Intel PROSet/Wireless WiFi Connection Utility:
1.Click Advanced > Adapter Settings > Advanced tab.
2.Windows 7 or 8*: Select Transmit Power, change Value to 5. Highest.
Note:If the slider is already at Highest / Maximum Performance, move the slider to another setting and then back to Highest / Maximum Performance

Set CAM using network control panel applet (NCPA)
Put the wireless adapter into continuously aware mode using the following steps:
1.Click Start > Settings > Control Panel.
2.Double-click Network Connections.
3.Right-click the wireless connection and click Properties.
4.Click Configure.
5.Click the Advanced tab.
6.Windows XP: Select the Power Management setting, uncheck Default / Auto, and move the slider to Highest / Maximum Performance.
7.Windows 7 or 8: Select Transmit Power, change Value to 5. Highest
Note:If the slider is already at Highest / Maximum Performance, move the slider to another setting and then back to Highest / Maximum Performance

Kudos to your thread.
Looks like quite complicated. Fortunately, I am NOT using a laptop with Intel 7260 wireless chipset.