Luis I am having the same problem. I ran EtreCheck, and here is the result:
EtreCheck version: 3.3.2 (395)
Report generated 2017-05-25 01:44:54
Download EtreCheck from https://etrecheck.com
Runtime: 2:30
Performance: Excellent
Click the [Lookup] links for more information from Apple Support Communities.
Click the [Details] links for more information about that line.
Problem: Other problem
Description:
App Store and Mail are not showing all content
Hardware Information: ⓘ
MacBook Air (13-inch, Early 2015)
[Technical Specifications] - [User Guide] - [Warranty & Service]
MacBook Air - model: MacBookAir7,2
1 1.6 GHz Intel Core i5 (i5-5250U) CPU: 2-core
8 GB RAM Not upgradeable
BANK 0/DIMM0
4 GB DDR3 1600 MHz ok
BANK 1/DIMM0
4 GB DDR3 1600 MHz ok
Bluetooth: Good - Handoff/Airdrop2 supported
Wireless: en0: 802.11 a/b/g/n/ac
Battery: Health = Normal - Cycle count = 203
Video Information: ⓘ
Intel HD Graphics 6000 - VRAM: 1536 MB
Color LCD 1440 x 900
System Software: ⓘ
macOS Sierra 10.12.5 (16F73) - Time since boot: about one hour
Disk Information: ⓘ
APPLE SSD SM0512G disk0 : (500.28 GB) (Solid State - TRIM: Yes)
[Show SMART report]
EFI (disk0s1 - MS-DOS FAT32) <not mounted> : 210 MB
Recovery HD (disk0s3 - Journaled HFS+) <not mounted> [Recovery]: 650 MB
Macintosh HD (disk1 - Journaled HFS+) / [Startup]: 499.06 GB (427.11 GB free)
Encrypted AES-XTS Unlocked
Core Storage: disk0s2 499.42 GB Online
USB Information: ⓘ
USB30Bus
Apple Inc. BRCM20702 Hub
Apple Inc. Bluetooth USB Host Controller
Thunderbolt Information: ⓘ
Apple Inc. thunderbolt_bus
Gatekeeper: ⓘ
Mac App Store and identified developers
Kernel Extensions: ⓘ
/Library/Application Support/MacKeeper/AntiVirus.app
[not loaded] com.mackeeper.kext.AVKauth (2.11 - SDK 10.10) [Lookup]
[not loaded] com.mackeeper.kext.AVKauth.Legacy (2.11 - SDK 10.10) [Lookup]
[loaded] com.mackeeper.kext.Firewall (2.11 - SDK 10.10) [Lookup]
[not loaded] com.mackeeper.kext.Firewall.Legacy (2.11 - SDK 10.10) [Lookup]
/Library/Extensions
[not loaded] com.seagate.driver.PowSecDriverCore (5.2.7 (26997) - SDK 10.4) [Lookup]
/Library/Extensions/Seagate Storage Driver.kext/Contents/PlugIns
[not loaded] com.seagate.driver.PowSecLeafDriver_10_4 (5.2.7 (26997) - SDK 10.4) [Lookup]
[not loaded] com.seagate.driver.PowSecLeafDriver_10_5 (5.2.7 (26997) - SDK 10.5) [Lookup]
[not loaded] com.seagate.driver.SeagateDriveIcons (5.2.7 (26997) - SDK 10.4) [Lookup]
System Launch Agents: ⓘ
[not loaded] 6 Apple tasks
[loaded] 184 Apple tasks
[running] 92 Apple tasks
System Launch Daemons: ⓘ
[not loaded] 37 Apple tasks
[loaded] 175 Apple tasks
[running] 105 Apple tasks
Launch Agents: ⓘ
[running] com.motive.alertDetectorHost.plist (? 84ce405e c05c55ca - installed 2015-09-27) [Lookup]
[running] com.motive.userAgent.plist (Shell Script fce7c274 - installed 2015-09-27) [Lookup]
[running] com.trusteer.rapport.rapportd.plist (Trusteer LTD - installed 2017-04-05) [Lookup]
Launch Daemons: ⓘ
[loaded] com.adobe.fpsaud.plist (? 2afb3af7 77ec3a65 - installed 2017-04-26) [Lookup]
[running] com.mackeeper.AntiVirus.plist (KROMTECH ALLIANCE CORP. - installed 2017-02-23) [Lookup]
[running] com.mackeeper.MacKeeper.plugin.AntiTheft.daemon.plist (KROMTECH ALLIANCE CORP. - installed 2017-05-08) [Lookup]
[running] com.motive.systemDaemon.plist (Shell Script 254d0f75 - installed 2015-09-27) [Lookup]
[running] com.seagate.TBDecorator.plist (? 595582c 1b6889ee - installed 2016-03-31) [Lookup]
[running] com.trusteer.rooks.rooksd.plist (Trusteer LTD - installed 2017-03-16) [Lookup]
User Launch Agents: ⓘ
[loaded] com.google.keystone.agent.plist (Google, Inc. - installed 2017-03-28) [Lookup]
[running] com.mackeeper.MacKeeper.Helper.plist (KROMTECH ALLIANCE CORP. - installed 2017-05-19) [Lookup]
Internet Plug-ins: ⓘ
npMotive: 1.0.0 (installed 2015-01-22) [Lookup]
FlashPlayer-10.6: 25.0.0.171 (installed 2017-05-10) [Lookup]
QuickTime Plugin: 7.7.3 (installed 2017-05-23)
AdobePDFViewerNPAPI: 11.0.10 (installed 2014-12-02) [Lookup]
AdobePDFViewer: 11.0.10 (installed 2014-12-02) [Lookup]
Flash Player: 25.0.0.171 (installed 2017-05-10) [Lookup]
Silverlight: 5.1.30514.0 (installed 2015-01-18) [Lookup]
JavaAppletPlugin: 15.0.1 (installed 2015-04-22) Check version
User internet Plug-ins: ⓘ
Dashlane: Dashlane 1.0.0 (installed 2014-02-07) [Lookup]
Safari Extensions: ⓘ
[enabled] AdBlock - BetaFish, Inc. - https://getadblock.com (installed 2015-09-27)
3rd Party Preference Panes: ⓘ
Flash Player (installed 2017-04-26) [Lookup]
Seagate Dashboard for Mac OSX (installed 2016-05-06) [Lookup]
Time Machine: ⓘ
Skip System Files: NO
Mobile backups: ON
Auto backup: YES
Volumes being backed up:
Macintosh HD: Disk size: 499.06 GB Disk used: 71.95 GB
Destinations:
Seagate Backup Plus Drive [Local]
Total size: 999.86 GB
Total number of backups: 32
Oldest backup: 9/12/15, 1:47 PM
Last backup: 5/22/17, 11:41 PM
Size of backup disk: Adequate
Backup size 999.86 GB > (Disk used 71.95 GB X 3)
Top Processes by CPU: ⓘ
6% WindowServer -daemon
2% hidd
0% syncdefaultsd
0% fontd
0% com.apple.iCloudHelper
Top Processes by Memory: ⓘ
418 MB MacKeeper Helper
385 MB AntiVirus
270 MB Google Chrome Helper --type=renderer [and 15 more arguments]
205 MB Finder
197 MB Google Chrome Helper --type=gpu-process [and 15 more arguments]
Top Processes by Network Use: ⓘ
Input Output Process name
153 KB 2 KB com.apple.geod
34 KB 44 KB mDNSResponder
10 KB 24 KB apsd
26 KB 0 B UserExecutor.js
5 KB 19 KB assistantd
Top Processes by Energy Use: ⓘ
6.74 WindowServer -daemon
1.74 hidd
0.58 Main.js
0.36 syncdefaultsd
Virtual Memory Information: ⓘ
2.98 GB Available RAM
1.76 GB Free RAM
5.02 GB Used RAM
1.22 GB Cached files
0 B Swap Used
Diagnostics Information: ⓘ
2017-05-25 01:02:39 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-25-010239_ [redacted].crash
/System/Library/Frameworks/WebKit.framework/Versions/A/XPCServices/com.apple.We bKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent
2017-05-25 01:00:34 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-25-010034_ [redacted].crash
2017-05-25 00:56:58 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-25-005658_ [redacted].crash
2017-05-24 23:33:20 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-24-233320_ [redacted].crash
2017-05-24 23:17:25 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-24-231725_ [redacted].crash
2017-05-24 23:16:10 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-24-231610_ [redacted].crash
2017-05-24 23:13:59 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-24-231359_ [redacted].crash
2017-05-24 23:13:08 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-24-231308_ [redacted].crash
2017-05-24 23:09:02 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-24-230902_ [redacted].crash
2017-05-24 23:04:31 ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2017-05-24-230431_ [redacted].crash